Latest Articles from Comparative Cytogenetics Latest 100 Articles from Comparative Cytogenetics https://compcytogen.pensoft.net/ Thu, 28 Mar 2024 18:54:47 +0200 Pensoft FeedCreator https://compcytogen.pensoft.net/i/logo.jpg Latest Articles from Comparative Cytogenetics https://compcytogen.pensoft.net/ An updated Atlas of Helophorus chromosomes https://compcytogen.pensoft.net/article/112831/ Comparative Cytogenetics 17: 295-326

DOI: 10.3897/compcytogen.17.112831

Authors: Robert B. Angus

Abstract: An account is given of my development of techniques to obtain well-spread Giemsa-stained banded chromosome preparations. Apparent G-banding could be obtained following very slight trypsin treatment of freshly prepared slides, but this banding was very fine (close-grained) and possibly not a reflection of chromosome structure. However, treatment of developing embryos in vitro with 5-fluorouridine produced a similar chromomere banding, which is therefore regarded as genuine. Steady accumulation of Helophorus Fabricius, 1775 karyotypes has resulted in the production of an Atlas covering 62 of the 170 species known to occur in the Palaearctic. Chromosome polymorphisms involving pericentric inversions and addition of extra C-banding regions have been found, as well as small B-chromosomes in a few species. In general, karyotypes have proved very useful in establishing the limits of individual species. Parthenogenesis involving triploidy has been found in two species. Karyotypes of experimentally produced hybrids have revealed irregularities in chromosome condensation.

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Research Article Thu, 21 Dec 2023 18:11:50 +0200
Karyotype and reproductive traits of the unique symbiotic mealybug Orbuspedum machinator G.-Z. (Homoptera, Coccinea) https://compcytogen.pensoft.net/article/116550/ Comparative Cytogenetics 17: 283-286

DOI: 10.3897/compcytogen.17.116550

Authors: Ilya A. Gavrilov-Zimin

Abstract: The karyotype and reproductive features of Orbuspedum machinator Gavrilov-Zimin, 2017 (Pseudococcidae) were studied for the first time. Diploid chromosome number is 18 in females. Reproduction is probably bisexual, as indicated by the presence of characteristic Lecanoid heterochromatinization of the paternal set of chromosomes in embryonic cells of about 50% of the embryos studied. The female reproductive system has a pair of lateral oviducts merged into enlarged common oviduct; the spermatheca and accessory glands are connected to the common oviduct in its proximal part. Complete ovoviviparity occurs in ontogenesis.

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Short Communication Mon, 18 Dec 2023 15:54:01 +0200
A comparative cytogenetic study of Hypsibarbus malcolmi and H. wetmorei (Cyprinidae, Poropuntiini) https://compcytogen.pensoft.net/article/107703/ Comparative Cytogenetics 17: 181-194

DOI: 10.3897/compcytogen.17.107703

Authors: Sudarat Khensuwan, Weerayuth Supiwong, Chatmongkon Suwannapoom, Phichaya Buasriyot, Sitthisak Jantarat, Weera Thongnetr, Nawarat Muanglen, Puntivar Kaewmad, Pasakorn Saenjundaeng, Kriengkrai Seetapan, Thomas Liehr, Alongklod Tanomtong

Abstract: Cyprininae are a highly diversified but demonstrably monophyletic lineage of cypriniform fishes. Here, the karyotype and chromosomal characteristics of Hypsibarbus malcolmi (Smith, 1945) and H. wetmorei (Smith, 1931) were examined using conventional, nucleolus organizing regions (NORs) and molecular cytogenetic protocols. The diploid chromosome number (2n) of H. malcolmi was 50, the fundamental number (FN) was equal to 62, and the karyotype displayed 8m + 4sm + 38a with NORs located at the centromeric and telomeric positions of the short arms of chromosome pairs 1 and 2, respectively. 2n of H. wetmorei was 50, FN 78, karyotype 14m + 14sm + 22a with the NORs at the telomeric position of the short arm of chromosome pair 2. 2n and FN in males and females were identical. Fluorescence in situ hybridization using different microsatellite motifs as probes also showed substantial genomic divergence between both studied species. In H. wetmorei, (CAG)n and (CAC)n microsatellites accumulated in the telomeric regions of all chromosomes, while in H. malcolmi, they had scattered signals on all chromosomes. Besides, the (GAA)n microsatellites were distributed along all chromosomes of H. malcolmi, but there was a strong hybridization pattern in the centromeric region of a single pair in H. wetmorei. These cytogenomic difference across the genomes of these Hypsibarbus Rainboth, 1996 species are markers for specific evolutionary differentiation within these two species.

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Research Article Fri, 15 Sep 2023 13:57:56 +0300
Complete chloroplast genome sequence of Rhododendron mariesii and comparative genomics of related species in the family Ericaeae https://compcytogen.pensoft.net/article/101427/ Comparative Cytogenetics 17: 163-180

DOI: 10.3897/compcytogen.17.101427

Authors: Zhiliang Li, Zhiwei Huang, Xuchun Wan, Jiaojun Yu, Hongjin Dong, Jialiang Zhang, Chunyu Zhang, Shuzhen Wang

Abstract: Rhododendron mariesii Hemsley et Wilson, 1907, a typical member of the family Ericaeae, possesses valuable medicinal and horticultural properties. In this research, the complete chloroplast (cp) genome of R. mariesii was sequenced and assembled, which proved to be a typical quadripartite structure with the length of 203,480 bp. In particular, the lengths of the large single copy region (LSC), small single copy region (SSC), and inverted repeat regions (IR) were 113,715 bp, 7,953 bp, and 40,918 bp, respectively. Among the 151 unique genes, 98 were protein-coding genes, 8 were tRNA genes, and 45 were rRNA genes. The structural characteristics of the R. mariesii cp genome was similar to other angiosperms. Leucine was the most representative amino acid, while cysteine was the lowest representative. Totally, 30 codons showed obvious codon usage bias, and most were A/U-ending codons. Six highly variable regions were observed, such as trnK-pafI and atpE-rpoB, which could serve as potential markers for future barcoding and phylogenetic research of R. mariesii species. Coding regions were more conserved than non-coding regions. Expansion and contraction in the IR region might be the main length variation in R. mariesii and related Ericaeae species. Maximum-likelihood (ML) phylogenetic analysis revealed that R. mariesii was relatively closed to the R. simsii Planchon, 1853 and R. pulchrum Sweet,1831. This research will supply rich genetic resource for R. mariesii and related species of the Ericaeae.

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Research Article Fri, 18 Aug 2023 18:16:41 +0300
Allium cytogenetics: a critical review on the Indian taxa https://compcytogen.pensoft.net/article/98903/ Comparative Cytogenetics 17: 129-156

DOI: 10.3897/CompCytogen.17.98903

Authors: Biplab Kumar Bhowmick, Sayantika Sarkar, Dipasree Roychowdhury, Sayali D. Patil, Manoj M. Lekhak, Deepak Ohri, Satyawada Rama Rao, S. R. Yadav, R. C. Verma, Manoj K. Dhar, S. N. Raina, Sumita Jha

Abstract: The genus Allium Linnaeus, 1753 (tribe Allieae) contains about 800 species worldwide of which almost 38 species are reported in India, including the globally important crops (onion, garlic, leek, shallot) and many wild species. A satisfactory chromosomal catalogue of Allium species is missing which has been considered in the review for the species occurring in India. The most prominent base number is x=8, with few records of x=7, 10, 11. The genome size has sufficient clues for divergence, ranging from 7.8 pg/1C to 30.0 pg/1C in diploid and 15.16 pg/1C to 41.78 pg/1C in polyploid species. Although the karyotypes are seemingly dominated by metacentrics, substantial variation in nucleolus organizing regions (NORs) is noteworthy. The chromosomal rearrangement between A. cepa Linnaeus, 1753 and its allied species has paved way to appreciate genomic evolution within Allium. The presence of a unique telomere sequence and its conservation in Allium sets this genus apart from all other Amaryllids and supports monophyletic origin. Any cytogenetic investigation regarding NOR variability, telomere sequence and genome size in the Indian species becomes the most promising field to decipher chromosome evolution against the background of species diversity and evolution, especially in the Indian subcontinent.

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Review Article Mon, 29 May 2023 15:42:26 +0300
More hidden diversity in a cryptic species complex: a new subspecies of Leptidea sinapis (Lepidoptera, Pieridae) from Northern Iran https://compcytogen.pensoft.net/article/102830/ Comparative Cytogenetics 17: 113-128

DOI: 10.3897/compcytogen.17.102830

Authors: Vazrick Nazari, Vladimir A. Lukhtanov, Alireza Naderi, Zdenek Faltýnek Fric, Vlad Dincă, Roger Vila

Abstract: A new subspecies of Leptidea sinapis from Northern Iran, discovered by means of DNA barcoding, is described as Leptidea sinapis tabarestana ssp. nov. The new subspecies is allopatric with respect to other populations of L. sinapis and is genetically distinct, appearing as a well-supported sister clade to all other populations in COI-based phylogenetic reconstructions. Details on karyotype, genitalia, ecology and behaviour for the new subspecies are given and a biogeographical speciation scenario is proposed.

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Research Article Thu, 4 May 2023 17:34:42 +0300
Comparative karyotype analysis of eight Cucurbitaceae crops using fluorochrome banding and 45S rDNA-FISH https://compcytogen.pensoft.net/article/99236/ Comparative Cytogenetics 17: 31-58

DOI: 10.3897/compcytogen.v17.i1.99236

Authors: Chao-Wen She, Xiang-Hui Jiang, Chun-Ping He

Abstract: To have an insight into the karyotype variation of eight Cucurbitaceae crops including Cucumis sativus Linnaeus, 1753, Cucumis melo Linnaeus, 1753, Citrullus lanatus (Thunberg, 1794) Matsumura et Nakai, 1916, Benincasa hispida (Thunberg, 1784) Cogniaux, 1881, Momordica charantia Linnaeus, 1753, Luffa cylindrica (Linnaeus, 1753) Roemer, 1846, Lagenaria siceraria var. hispida (Thunberg, 1783) Hara, 1948 and Cucurbita moschata Duchesne ex Poiret, 1819, well morphologically differentiated mitotic metaphase chromosomes were prepared using the enzymatic maceration and flame-drying method, and the chromosomal distribution of heterochromatin and 18S-5.8S-26S rRNA genes (45S rDNA) was investigated using sequential combined PI and DAPI (CPD) staining and fluorescence in situ hybridization (FISH) with 45S rDNA probe. Detailed karyotypes were established using the dataset of chromosome measurements, fluorochrome bands and rDNA FISH signals. Four karyotype asymmetry indices, CVCI, CVCL, MCA and Stebbins’ category, were measured to elucidate the karyological relationships among species. All the species studied had symmetrical karyotypes composed of metacentric and submetacentric or only metacentric chromosomes, but their karyotype structure can be discriminated by the scatter plot of MCA vs. CVCL. The karyological relationships among these species revealed by PCoA based on x, 2n, TCL, MCA, CVCL and CVCI was basically in agreement with the phylogenetic relationships revealed by DNA sequences. CPD staining revealed all 45S rDNA sites in all species, (peri)centromeric GC-rich heterochromatin in C. sativus, C. melo, C. lanatus, M. charantia and L. cylindrica, terminal GC-rich heterochromatin in C. sativus. DAPI counterstaining after FISH revealed pericentromeric DAPI+ heterochromatin in C. moschata. rDNA FISH detected two 45S loci in five species and five 45S loci in three species. Among these 45S loci, most were located at the terminals of chromosome arms, and a few in the proximal regions. In C. sativus, individual chromosomes can be precisely distinguished by the CPD band and 45S rDNA signal patterns, providing an easy method for chromosome identification of cucumber. The genome differentiation among these species was discussed in terms of genome size, heterochromatin, 45S rDNA site, and karyotype asymmetry based on the data of this study and previous reports.

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Research Article Thu, 9 Feb 2023 17:40:12 +0200
Chromosome complements of Channa lucius and C. striata from Phu Quoc Island and karyotypic evolution in snakehead fishes (Actinopterygii, Channidae) https://compcytogen.pensoft.net/article/94943/ Comparative Cytogenetics 17: 1-12

DOI: 10.3897/compcytogen.v17.i1.94943

Authors: Denis V. Prazdnikov

Abstract: Snakehead fishes of the family Channidae are obligatory air-breathers freshwater predators, the vast majority of which belong to the genus Channa Scopoli, 1777. Channa species are characterized by high karyotypic diversity due to various types of chromosomal rearrangements. It is assumed that, in addition to the lifestyle, fragmentation and isolation of snakehead populations contribute to an increase in karyotypic diversity. However, the chromosome complements of many isolated populations of widespread Channa species remain unknown, and the direction of karyotype transformations is poorly understood. This paper describes the previously unstudied karyotypes of Channa lucius (Cuvier, 1831) and C. striata (Bloch, 1793) from Phu Quoc Island and analyzes the trends of karyotypic evolution in the genus Channa. In C. lucius, the karyotypes are differed in the number of chromosome arms (2n = 48, NF = 50 and 51), while in C. striata, the karyotypes are differed in the diploid chromosome number (2n = 44 and 43, NF = 48). A comparative cytogenetic analysis showed that the main trend of karyotypic evolution of Channa species is associated with a decrease in the number of chromosomes and an increase in the number of chromosome arms, mainly due to fusions and pericentric inversions. The data obtained support the assumption that fragmentation and isolation of populations, especially of continental islands, contribute to the karyotypic diversification of snakeheads and are of interest for further cytogenetic studies of Channidae.

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Research Article Tue, 3 Jan 2023 10:07:04 +0200
Chromosomal polymorphism in natural populations of Chironomus sp. prope agilis Kiknadze, Siirin, Filippova et al., 1991 (Diptera, Chironomidae) https://compcytogen.pensoft.net/article/95659/ Comparative Cytogenetics 16(4): 243-252

DOI: 10.3897/compcytogen.v16.i4.95659

Authors: Veronika V. Golygina

Abstract: Species Chironomus sp. prope agilis Kiknadze, Siirin, Filippova et al., 1991 belongs to the Ch. plumosus group of sibling species. It was described on the basis of its karyotype and analysis of isozymes from one population in the Urals but since then no quantitative data on chromosomal polymorphism of this species have been published. The goal of this study is to broaden our knowledge of the chromosomal polymorphism and distribution of the Chironomus sp. prope agilis, which, along with the data on chromosomal polymorphism of other species from the Ch. plumosus group, can give us a better understanding of the connection between chromosomal polymorphism and ecological conditions of habitats. The specimens of Chironomus sp. prope agilis were found only in 8 natural populations from the Urals, Western Siberia and Kazakhstan, which allows us to conclude that the species range of Chironomus sp. prope agilis is not as wide as for most other species from Ch. plumosus group. An analysis of chromosomal polymorphism in these 8 natural populations of Chironomus sp. prope agilis has been performed. All of the studied populations were either monomorphic or showed very low level of chromosomal polymorphism, with 4.4–8.7% of heterozygous specimens per population and 0.04–0.08 heterozygotic inversion per larvae. The total number of banding sequences found in the banding sequence pool of Chironomus sp. prope agilis is 10. The mapping of banding sequence p’ag2B3 is presented for the first time. Besides inversions, one reciprocal translocation was found in a population from Kazakhstan, B-chromosome was found in one population from the Urals region of Russia, and heterozygosity of the level of expression of Balbiany rings in arm G was observed in several studied populations.

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Research Article Fri, 16 Dec 2022 15:09:35 +0200
A critical review on cytogenetics of Cucurbitaceae with updates on Indian taxa https://compcytogen.pensoft.net/article/79033/ Comparative Cytogenetics 16(2): 93-125

DOI: 10.3897/compcytogen.v16.i2.79033

Authors: Biplab Kumar Bhowmick, Sumita Jha

Abstract: The cytogenetic relationships in the species of Cucurbitaceae are becoming immensely important to answer questions pertaining to genome evolution. Here, a simplified and updated data resource on cytogenetics of Cucurbitaceae is presented on the basis of foundational parameters (basic, zygotic and gametic chromosome numbers, ploidy, genome size, karyotype) and molecular cytogenetics. We have revised and collated our own findings on seven agriculturally important Indian cucurbit species in a comparative account with the globally published reports. Chromosome count (of around 19% species) shows nearly three-fold differences while genome size (of nearly 5% species) shows 5.84-fold differences across the species. There is no significant correlation between chromosome numbers and nuclear genome sizes. The possible trend of evolution is discussed here based on molecular cytogenetics data, especially the types and distribution of nucleolus organizer regions (NORs). The review supersedes the scopes of general chromosome databases and invites scopes for continuous updates. The offline resource serves as an exclusive toolkit for research and breeding communities across the globe and also opens scope for future establishment of web-database on Cucurbitaceae cytogenetics.

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Review Article Tue, 26 Apr 2022 11:14:11 +0300
Karyotypic analysis and isolation of four DNA markers of the scleractinian coral Favites pentagona (Esper, 1795) (Scleractinia, Anthozoa, Cnidaria) https://compcytogen.pensoft.net/article/79953/ Comparative Cytogenetics 16(1): 77-92

DOI: 10.3897/compcytogen.v16.i1.79953

Authors: Rei Kawakami, Takahiro Taguchi, Joshua Vacarizas, Masumi Ito, Takuma Mezaki, Akira Tominaga, Satoshi Kubota

Abstract: We performed conventional and molecular cytogenetic studies on the Favites pentagona Esper, 1795, a scleractinian coral mostly found along the west coast of Japan. Karyotype analysis of F. pentagona by G-banding revealed a karyogram containing a homogenously staining region (HSR) on chromosome 10 in more than 50% of the examined metaphase spreads. This HSR consisted of sequences from 18S ribosomal RNA (rRNA) genes, as demonstrated by fluorescence in situ hybridization (FISH) and DNA sequencing. We highlighted the development of four chromosomal FISH markers from repetitive genes such as U2 small nuclear RNA linked to 5S rRNA sequence (U2 snRNA-5S), 18S rRNA, histone H3, and uncharacterized gene FP-9X. The chromosomal locations of the U2 snRNA-5S and 18S RNA were on the terminal end of long arm of chromosomes 2 and 10, respectively, while the histone H3 and the uncharacterized gene were located near the centromeres of chromosomes 1 and 9, respectively. These FISH markers will improve the karyotyping of F. pentagona from mitotic preparations which helps in widening our understanding of coral genetic structure and chromosome organization. In addition, these improvements in karyotyping will provide the basis in constructing of chromosome-level genome assembly for F. pentagona.

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Research Article Tue, 5 Apr 2022 14:31:24 +0300
Karyotype characteristics and gene COI sequences of Chironomus bonus Shilova et Dzhvarsheishvili, 1974 (Diptera, Chironomidae) from the South Caucasus (Republic of Georgia, Paravani river) https://compcytogen.pensoft.net/article/79182/ Comparative Cytogenetics 16(1): 19-38

DOI: 10.3897/CompCytogen.v16.i1.79182

Authors: Mukhamed Kh. Karmokov

Abstract: The study presents data on the karyotype characteristics and the mitochondrial gene COI sequences of the non-biting midge Chironomus bonus Shilova et sDzhvarsheishvili 1974 (Diptera Chironomidae) from the South Caucasus. The species belongs to the Ch. plumosus group of sibling species one of the most widespread and successful groups in the genus Chironomus Meigen 1803. The karyotype of the studied population is monomorphic. The morphological and chromosomal characteristics of Ch. bonus from the Caucasus are similar to those previously described for this species (Kiknadze et al. 1991a). In the phylogenetic tree based on the COI gene sequences one can observe several clear clusters. We named them Palearctic Ch. plumosus Far Eastern Ch. borokensis-Ch. suwai and Nearctic Ch. entis-Ch. plumosus clusters. The calculated K2P genetic distances within each cluster have not exceeded the 3% threshold for the genus Chironomus. Contrary to this the distances between the clusters exceed this range and correspond to separate species. The Ch. bonus sequences belong to the cluster consisting of Ch. plumosus (Linnaeus 1758) sequences from European populations and do not form a separate clade of the phylogenetic tree. One can suppose that the origin of the Ch. plumosus group of sibling species dates back to 5.75–3.43 million years ago (Mya) the epochs of Late Miocene (7,3–5,3 Mya) and early Pliocene (5,3–2,58 Mya). On the other hand Palearctic Ch. plumosus Far Eastern Ch. borokensis-Ch. suwai and Nearctic Ch. entis-Ch. plumosus clusters appeared relatively recently in the Middle Pleistocene 1.288–0.307 Mya. The possible relationship between the climate changes in the Pliocene and the origin of the Ch. plumosus group are discussed. Chironomidae

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Research Article Tue, 1 Mar 2022 15:30:22 +0200
Revision of the banding sequence pool and new data on chromosomal polymorphism in natural populations of Chironomus agilis Shobanov et Djomin, 1988 (Diptera, Chironomidae) https://compcytogen.pensoft.net/article/76761/ Comparative Cytogenetics 15(4): 527-541

DOI: 10.3897/CompCytogen.v15.i4.76761

Authors: Veronika V. Golygina, Oksana V. Ermolaeva

Abstract: Quantitative and qualitative analysis of chromosomal polymorphism in 19 natural populations of Ch. agilis had been performed. Most studied populations showed a medium level of chromosomal polymorphism: on average 45±3.0% of specimens are heterozygotes with 0.52±0.01 heterozygotic inversion per larvae. Besides inversions, B-chromosomes were found in two populations. The total number of banding sequences found in banding sequence pool of Ch. agilis is 16. Three banding sequences – p’agiB3, p’agiD3, p’agiF3 – are described for the first time.

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Research Article Fri, 17 Dec 2021 09:45:09 +0200
A new species of the genus Rhaphidosoma Amyot et Serville, 1843 (Heteroptera, Reduviidae), with data on its chromosome complement https://compcytogen.pensoft.net/article/78718/ Comparative Cytogenetics 15(4): 467-505

DOI: 10.3897/CompCytogen.v15.i4.78718

Authors: Dmitry A. Gapon, Valentina G. Kuznetsova, Anna Maryańska-Nadachowska

Abstract: A new species, Rhaphidosoma paganicum sp. nov. (Heteroptera: Reduviidae: Harpactorinae: Rhaphidosomatini), is described from the Dry Zone of Myanmar. It is the fifth species of Rhaphidosoma Amyot et Serville, 1843, known from the Oriental Region, and the first record of the genus for Myanmar and Indochina. The structure of the external and internal terminalia of the male and female is described and illustrated in detail. The completely inflated endosoma is described for the first time in reduviids. The complex structure of the ductus seminis is shown; it terminates with a voluminous seminal chamber which opens with a wide secondary gonopore and may be a place where spermatophores are formed. The new species is compared with all congeners from the Oriental Region and Western Asia. It is characterised by the absence of distinct tubercles on the abdominal tergites of the male, the presence only two long tubercles and small rounded ones on the abdominal tergites VII and VI, respectively, in the female, the presence of short fore wing vestiges which are completely hidden under longer fore wing vestiges, and other characters. In addition to the morphological description, an account is given of the male karyotype and the structure of testes of Rh. paganicum sp. nov. and another species of Harpactorinae, Polididus armatissimus Stål, 1859 (tribe Harpactorini). It was found that Rh. paganicum sp. nov. has a karyotype comprising 12 pairs of autosomes and a multiple sex chromosome system (2n♂=24A+X1X2X3Y), whereas P. armatissimus has a karyotype comprising five pairs of autosomes and a simple sex chromosome system (2n♂=10A+XY). The males of these species were found to have seven and nine follicles per testis, respectively. FISH mapping of 18S ribosomal DNA (major rDNA) revealed hybridisation signals on two of the four sex chromosomes (Y and one of the Xs) in Rh. paganicum sp. nov. and on the largest pair of autosomes in P. armatissimus. The presence of the canonical “insect” (TTAGG)n telomeric repeat was detected in the chromosomes of both species. This is the first application of FISH in the tribe Raphidosomatini and in the genus Polididus Stål, 1858.

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Research Article Wed, 15 Dec 2021 15:03:22 +0200
A rare chromosomal polymorphism in a Kangayam bull (Bos indicus) of south India https://compcytogen.pensoft.net/article/71295/ Comparative Cytogenetics 15(4): 459-465

DOI: 10.3897/CompCytogen.v15.i4.71295

Authors: Vemula Harshini, P. Kumarasamy, S.M.K. Karthickeyan

Abstract: A chromosomal polymorphism was detected on karyological screening of Kangayam breeding sires prior to subjecting them for frozen semen collection. One bull possessed the chromosomal complement 2n = 60, consisting of 58 acrocentric autosomes, one large sub-metacentric X-chromosome, and one small acrocentric Y-chromosome with a small visible p-arm, which was further confirmed using CBG- and GTG-banding. This polymorphism was attributed to a heterochromatin variation of the acrocentric Y-chromosome routine in the Bos indicus Linnaeus, 1758 cattle.

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Short Communication Wed, 15 Dec 2021 11:45:00 +0200
Intraspecies multiple chromosomal variations including rare tandem fusion in the Russian Far Eastern endemic evoron vole Alexandromys evoronensis (Rodentia, Arvicolinae) https://compcytogen.pensoft.net/article/67112/ Comparative Cytogenetics 15(4): 393-411

DOI: 10.3897/compcytogen.v15.i4.67112

Authors: Irina V. Kartavtseva, Irina N. Sheremetyeva, Marina V. Pavlenko

Abstract: The vole Alexandromys evoronensis (Kovalskaya et Sokolov, 1980) with its two chromosomal races, “Evoron” (2n = 38–41, NF = 54–59) and “Argi” (2n = 34, 36, 37, NF = 51–56) is the endemic vole found in the Russian Far East. For the “Argi” chromosomal race, individuals from two isolated populations in mountain regions were investigated here for the first time using GTG-, GTC-, NOR methods. In the area under study, 8 new karyotype variants have been registered. The karyotype with 2n = 34 has a rare tandem fusion of three autosomes: two biarmed (Mev6 and Mev7) and one acrocentric (Mev14) to form a large biarmed chromosome (Mev6/7/14), all of which reveal a heterozygous state. For A. evoronensis, the variation in the number of chromosomes exceeded the known estimate of 2n = 34, 36 and amounted to 2n = 34, 36, 38–41. The combination of all the variations of chromosomes for the species made it possible to describe 20 variants of the A. evoronensis karyotype, with 11 chromosomes being involved in multiple structural rearrangements. In the “Evoron” chromosomal race 4 chromosomes (Mev1, Mev4, Mev17, and Mev18) and in the “Argi” chromosomal race 9 chromosomes (Mev6, Mev7, Mev14, Mev13, Mev11, Mev15, Mev17, Mev18, and Mev19) were observed. Tandem and Robertsonian rearrangements (Mev17/18 and Mev17.18) were revealed in both chromosomal races “Evoron” and “Argi”.

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Research Article Mon, 22 Nov 2021 10:00:16 +0200
The Kengyilia hirsuta karyotype polymorphisms as revealed by FISH with tandem repeats and single-gene probes https://compcytogen.pensoft.net/article/71525/ Comparative Cytogenetics 15(4): 375-392

DOI: 10.3897/compcytogen.v15.i4.71525

Authors: Xiaoyan Tao, Bo Liu, Quanwen Dou

Abstract: Kengyilia hirsuta (Keng, 1959) J. L. Yang, C. Yen et B. R. Baum, 1992, a perennial hexaploidy species, is a wild relative species to wheat with great potential for wheat improvement and domestication. The genome structure and cross-species homoeology of K. hirsuta chromosomes with wheat were assayed using 14 single-gene probes covering all seven homoeologous groups, and four repetitive sequence probes 45S rDNA, 5S rDNA, pAs1, and (AAG)10 by FISH. Each chromosome of K. hirsuta was well characterized by homoeological determination and repeats distribution patterns. The synteny of chromosomes was strongly conserved in the St genome, whereas synteny of the Y and P genomes was more distorted. The collinearity of 1Y, 2Y, 3Y and 7Y might be interrupted in the Y genome. A new 5S rDNA site on 2Y might be translocated from 1Y. The short arm of 3Y might involve translocated segments from 7Y. The 7 Y was identified as involving a pericentric inversion. A reciprocal translocation between 2P and 4P, and tentative structural aberrations in the subtelomeric region of 1PL and 4PL, were observed in the P genome. Chromosome polymorphisms, which were mostly characterized by repeats amplification and deletion, varied between chromosomes, genomes, and different populations. However, two translocations involving a P genome segmental in 3YL and a non-Robertsonial reciprocal translocation between 4Y and 3P were identified in two independent populations. Moreover, the proportion of heterozygous karyotypes reached almost 35% in all materials, and almost 80% in the specific population. These results provide new insights into the genome organization of K. hirsuta and will facilitate genome dissection and germplasm utilization of this species.

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Research Article Wed, 3 Nov 2021 18:58:29 +0200
Chromosomal and DNA barcode analysis of the Melitaea ala Staudinger, 1881 species complex (Lepidoptera, Nymphalidae) https://compcytogen.pensoft.net/article/66121/ Comparative Cytogenetics 15(2): 199-216

DOI: 10.3897/CompCytogen.v15.i2.66121

Authors: Vladimir A. Lukhtanov, Anastasia V. Gagarina, Elena A. Pazhenkova

Abstract: The species of the Melitaea ala Staudinger, 1881 complex are distributed in Central Asia. Here we show that this complex is a monophyletic group including the species, M. ala, M. kotshubeji Sheljuzhko, 1929 and M. enarea Fruhstorfer, 1917. The haploid chromosome number n=29 is found in M. ala and M. kotshubeji and is, most likely, a symplesiomorphy of the M. ala complex. We show that M. ala consists of four subspecies: M. ala zaisana Lukhtanov, 1999 (=M. ala irtyshica Lukhtanov, 1999, syn. nov.) (South Altai, Zaisan Lake valley), M. ala ala (Dzhungarian Alatau), M. ala bicolor Seitz, 1908 (North, East, Central and West Tian-Shan) and M. ala determinata Bryk, 1940 (described from “Fu-Shu-Shi”, China). We demonstrate that M. kotshubeji kotshubeji (Peter the Great Mts in Tajikistan) and M. kotshubeji bundeli Kolesnichenko, 1999 (Alai Mts in Tajikistan and Kyrgyzstan) are distinct taxa despite their geographic proximity in East Tajikistan. Melitaea enarea is widely distributed in the southern part of Central Asia and is sympatric with M. kotshubeji.

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Research Article Fri, 18 Jun 2021 12:39:11 +0300
Karyotype and COI sequences of Chironomus sokolovae Istomina, Kiknadze et Siirin, 1999 (Diptera,Chironomidae) from the bay of Orkhon River, Mongolia https://compcytogen.pensoft.net/article/66549/ Comparative Cytogenetics 15(2): 149-157

DOI: 10.3897/CompCytogen.v15.i2.66549

Authors: Viktor V. Bolshakov, Alexander A. Prokin

Abstract: Chironomus sokolovae Istomina, Kiknadze et Siirin, 1999 (Diptera, Chironomidae) is recorded from Mongolia for the first time. Eleven banding sequences determined in the Mongolian population were previously known from Altai and Yenisei populations: sokA1, sokB1, sokB2, sokC1, sokC2, sokD1, sokD2, sokE1, sokF1, sokF2 and sokG1. The additional B-chromosomes are absent. DNA-barcoding of COI gene was carried out for this species for the first time. The phylogenetic tree estimated by Bayesian inference showed a high similarity of the studied species with Ch. acutiventris Wülker, Ryser et Scholl, 1983 from the Chironomus obtusidens-group. The estimated genetic distance K2P between Ch. sokolovae and Ch. acutiventris is much lower (0.38%) than the commonly accepted threshold of 3% for species of genus Chironomus Meigen, 1803. Our results show that the accepted cytogenetic criteria of species level in the genus Chironomus are more in accordance with morphological ones of the same level, than with molecular-genetic criteria accepted for species COI genetic distance.

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Research Article Thu, 27 May 2021 14:22:51 +0300
Genome size variation and karyotype diversity in eight taxa of Sorbus sensu stricto (Rosaceae) from China https://compcytogen.pensoft.net/article/58278/ Comparative Cytogenetics 15(2): 137-148

DOI: 10.3897/CompCytogen.v15.i2.58278

Authors: Jiabao Li, Kailin Zhu, Qin Wang, Xin Chen

Abstract: Eight taxa of Sorbus Linnaeus, 1753 sensu stricto (Rosaceae) from China have been studied karyologically through chromosome counting, chromosomal measurement and karyotype symmetry. Genome size was also estimated by flow cytometry. Six taxa, S. amabilis Cheng ex T.T.Yu et K.C.Kuan, 1963, S. hupehensis var. paucijuga (D.K. Zang et P.C. Huang, 1992) L.T. Lu, 2000, S. koehneana C.K. Schneider, 1906, S. pohuashanensis (Hance, 1875) Hedlund, 1901, S. scalaris Koehne, 1913 and S. wilsoniana C.K. Schneider, 1906 are diploids with 2n = 34, whereas two taxa, S. filipes Handel-Mazzetti,1933 and S. ovalis McAllister, 2005 are tetraploid with 2n = 68. In general, the chromosome size is mainly small, and karyotypes are symmetrical with predominance of metacentric chromosomes. Genome size variation of diploids and tetraploids is 1.401 pg –1.676 pg and 2.674 pg –2.684 pg, respectively. Chromosome numbers of S. amabilis and S. hupehensis var. paucijuga, and karyotype and genome size of eight taxa studied are reported for the first time. This study emphasised the reliability of flow cytometry in genome size determination to infer ploidy levels in Chinese native Sorbus species.

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Research Article Thu, 20 May 2021 17:09:02 +0300
Comparative study of four Mystus species (Bagridae, Siluriformes) from Thailand: insights into their karyotypic diversity https://compcytogen.pensoft.net/article/60649/ Comparative Cytogenetics 15(2): 119-136

DOI: 10.3897/CompCytogen.v15.i2.60649

Authors: Pun Yeesin, Phichaya Buasriyot, Sukhonthip Ditcharoen, Patcharaporn Chaiyasan, Chatmongkon Suwannapoom, Sippakorn Juntaree, Sitthisak Jantarat, Sucheela Talumphai, Marcelo de Bello Cioffi, Thomas Liehr, Alongklod Tanomtong, Weerayuth Supiwong

Abstract: Karyotypes of four catfishes of the genus Mystus Scopoli, 1777 (family Bagridae), M. atrifasciatus Fowler, 1937, M. mysticetus Roberts, 1992, M. singaringan (Bleeker, 1846) and M. wolffii (Bleeker, 1851), were analysed by conventional and Ag-NOR banding as well as fluorescence in situ hybridization (FISH) techniques. Microsatellite d(GC)15, d(CAA)10, d(CAT)10 and d(GAA)10 repeat probes were applied in FISH. The obtained data revealed that the four studied species have different chromosome complements. The diploid chromosome numbers (2n) and the fundamental numbers (NF) range between 52 and 102, 54 and 104, 56 and 98, or 58 and 108 in M. mysticetus, M. atrifasciatus, M. singaringan or M. wolffii, respectively. Karyotype formulae of M. mysticetus, M. atrifasciatus, M. singaringan and M. wolffii are 24m+26sm+4a, 26m+24sm+2a, 24m+18sm+14a and 30m+22sm+6a, respectively. A single pair of NORs was identified adjacent to the telomeres of the short arm of chromosome pairs 3 (metacentric) in M. atrifasciatus, 20 (submetacentric) in M. mysticetus, 15 (submetacentric) in M. singaringan, and 5 (metacentric) in M. wolffii. The d(GC)15, d(CAA)10, d(CAT)10 and d(GAA)10 repeats were abundantly distributed in species-specific patterns. Overall, we present a comparison of cytogenetic and molecular cytogenetic patterns of four species from genus Mystus providing insights into their karyotype diversity in the genus.

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Research Article Mon, 26 Apr 2021 21:57:42 +0300
Cloning and physical localization of male-biased repetitive DNA sequences in Spinacia oleracea (Amaranthaceae) https://compcytogen.pensoft.net/article/63061/ Comparative Cytogenetics 15(2): 101-118

DOI: 10.3897/CompCytogen.v15.i2.63061

Authors: Jian Zhou, Shaojing Wang, Li'ang Yu, Ning Li, Shufen Li, Yulan Zhang, Ruiyun Qin, Wujun Gao, Chuanliang Deng

Abstract: Spinach (Spinacia oleracea Linnaeus, 1753) is an ideal material for studying molecular mechanisms of early-stage sex chromosome evolution in dioecious plants. Degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR) technique facilitates the retrotransposon-relevant studies by enriching specific repetitive DNA sequences from a micro-dissected single chromosome. We conducted genomic subtractive hybridization to screen sex-biased DNA sequences by using the DOP-PCR amplification products of micro-dissected spinach Y chromosome. The screening yielded 55 male-biased DNA sequences with 30 576 bp in length, of which, 32 DNA sequences (12 049 bp) contained repeat DNA sequences, including LTR/Copia, LTR/Gypsy, simple repeats, and DNA/CMC-EnSpm. Among these repetitive DNA sequences, four DNA sequences that contained a fragment of Ty3-gypsy retrotransposons (SP73, SP75, SP76, and SP77) were selected as fluorescence probes to hybridization on male and female spinach karyotypes. Fluorescence in situ hybridization (FISH) signals of SP73 and SP75 were captured mostly on the centromeres and their surrounding area for each homolog. Hybridization signals primarily appeared near the putative centromeres for each homologous chromosome pair by using SP76 and SP77 probes for FISH, and sporadic signals existed on the long arms. Results can be served as a basis to study the function of repetitive DNA sequences in sex chromosome evolution in spinach.

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Research Article Fri, 23 Apr 2021 10:57:06 +0300
Cytogenetic characterisation and chromosomal mapping of microsatellite and telomeric repeats in two gecko species (Reptilia, Gekkonidae) from Thailand https://compcytogen.pensoft.net/article/58208/ Comparative Cytogenetics 15(1): 41-52

DOI: 10.3897/CompCytogen.v15.i1.58208

Authors: Weera Thongnetr, Surachest Aiumsumang, Rodjarin Kongkaew, Alonglod Tanomtong, Chatmongkon Suwannapoom, Sumalee Phimphan

Abstract: Studies of chromosomes of Cyrtodactylus jarujini Ulber, 1993 and C. doisuthep Kunya et al., 2014 to compare microsatellite and TTAGGG sequences by classical and molecular techniques were conducted in Thailand. Karyological typing from a conventional staining technique of C. jarujini and C. doisuthep showed diploid chromosome numbers of 40 and 34 while the Fundamental Numbers (NF) were 56 in both species. In addition, we created the chromosome formula of the chromosomes of C. jarujini showing that 2n (40) = Lsm1 + Lsm2 + Lt3 + Mm1 + Mt4 + Sm2 + Sa2 + St5 while that of C. doisuthep was 2n (34) = Lsm3 + Lm2 + Lt3 + Mm1 + Mt2 + Sm4 + Sa1 + St1. Ag-NOR staining revealed NOR-bearing chromosomes in chromosome pairs 13 and 14 in C. jarujini, and in chromosome pairs 9 and 13 in C. doisuthep. This molecular study used the FISH technique, as well as microsatellite probes including (A)20, (TA)15, (CGG)10, (CGG)10, (GAA)10, (TA)15 and TTAGGG repeats. The signals showed that the different patterns in each chromosome of the Gekkonids depended on probe types. TTAGGG repeats showed high distribution on centromere and telomere regions, while (A)20, (TA)15, (CGG)10, (CGG)10, (GAA)10 and (TA)15 bearing dispersed over the whole genomes including chromosomes and some had strong signals on only a pair of homologous chromosomes. These results suggest that the genetic linkages have been highly differentiated between the two species.

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Research Article Tue, 2 Feb 2021 15:39:13 +0200
Comparative karyotype study of three Cyprinids (Cyprinidae, Cyprininae) in Thailand by classical cytogenetic and FISH techniques https://compcytogen.pensoft.net/article/54428/ Comparative Cytogenetics 14(4): 597-612

DOI: 10.3897/CompCytogen.v14i4.54428

Authors: Sumalee Phimphan, Patcharaporn Chaiyasan, Chatmongkon Suwannapoom, Montri Reungsing, Sippakorn Juntaree, Alongklod Tanomtong, Weerayuth Supiwong

Abstract: Three species of ornamental fishes in the subfamily Cyprininae (family Cyprinidae) namely, Epalzeorhynchos frenatum (Fowler, 1934), Puntigrus partipentazona (Fowler, 1934), Scaphognathops bandanensis Boonyaratpalin et Srirungroj, 1971 were studied by classical cytogenetic and fluorescent in situ hybridization (FISH) techniques. Chromosomes were directly prepared from kidney tissues and stained by using conventional and Ag-NOR banding techniques. Microsatellite d(CA)15 and d(CGG)10 probes were hybridized to the chromosomes of three cyprinids. The results show that the three cyprinid species share the same diploid number as 2n=50 but there are differences in the fundamental number (NF) and karyotypes i.e. E. frenatum: NF = 78, 18m+10sm+10st+12a; P. partipentazona: NF = 80, 6m+24sm+14st+6a; S. bandanensis: NF = 66, 4m+12sm+34a. NOR positive masks were observed at the regions adjacent to the telomere of the short arm of the chromosome pairs 10 (submetacentric) and 1 (metacentric) in E. frenatum and P. partipentazona, respectively whereas those were revealed at telomeric regions of the long arm of the chromosome pair 9 (acrocentric) in S. bandanensis. The mapping of d(CA)15 and d(CGG)10 microsatellites shown that hybridization signals are abundantly distributed in telomeric regions of several pairs except d(CA)15 repeats in S. bandanensis, which are distributed throughout all chromosomes and d(CGG)10 repeats in P. partipentazona display the high accumulation only in the first chromosome pair.

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Research Article Tue, 22 Dec 2020 13:30:55 +0200
Karyotype and DNA barcode of Polyommatus (Agrodiaetus) cyaneus (Staudinger, 1899) from its type locality: implication for taxonomic and evolutionary research in Polyommatus blue butterflies (Lepidoptera, Lycaenidae) https://compcytogen.pensoft.net/article/59574/ Comparative Cytogenetics 14(4): 567-575

DOI: 10.3897/CompCytogen.v14.i4.59574

Authors: Vladimir A. Lukhtanov, Alexander V. Dantchenko, Karine V. Balayan, Anastasia V. Gagarina

Abstract: Chromosomal and molecular analyses of rapidly evolving organisms such as Polyommatus Latreille, 1804 blue butterflies are essential for understanding their taxonomy and evolutionary history, and the studies of populations from their type localities are crucially important for resolving problems of nomenclature and species identity. Here we present data on the topotypical population of the blue butterfly species described as Lycaena damone var. cyanea Staudinger, 1899. This taxon was described from Khankendi (Nagorno-Karabakh, Caucasus), and rediscovered at the type locality for the first time since it was collected there in 1869. The specimens were found on dry stony meadows with a predominance of Onobrychis radiata Bieberstein, 1810, on upper border of oak forests. Their haploid chromosome number (n) was established as n = 17. Chromosomal and mitochondrial DNA barcode analyses of the studied samples from type-locality provided an opportunity for the critical taxonomic re-examination of Caucasian species of the subgenus Agrodiaetus Hübner, 1822 of the genus Polyommatus Latreille, 1804. The obtained data support the interpretation of the P. (A.) cyaneus (Staudinger, 1899) and P. (A.) carmon (Herrich-Schäffer, 1851) as two different, not closely related species complexes as previously hypothesized by Hugo de Lesse. On the contrary, the treatment by Walter Forster who considered these taxa as two groups of conspecific populations was not supported by our data.

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Short Communication Tue, 17 Nov 2020 22:04:11 +0200
Karyotypes diversity in some Iranian Pamphagidae grasshoppers (Orthoptera, Acridoidea, Pamphagidae): new insights on the evolution of the neo-XY sex chromosomes https://compcytogen.pensoft.net/article/53688/ Comparative Cytogenetics 14(4): 549-566

DOI: 10.3897/compcytogen.v14.i4.53688

Authors: Olesya Buleu, Ilyas Jetybayev, Mohsen Mofidi-Neyestanak, Alexander Bugrov

Abstract: For the first time, cytogenetic features of grasshoppers from Iran have been studied. In this paper we conducted a comparative cytogenetic analysis of six species from the family Pamphagidae. The species studied belong to subfamilies Thrinchinae Stål, 1876 (Eremopeza bicoloripes (Moritz, 1928), E. saussurei (Uvarov, 1918)) and Pamphaginae (Saxetania paramonovi (Dirsh, 1927), Tropidauchen escalerai Bolívar, 1912, Tropidauchen sp., and Paranothrotes citimus Mistshenko, 1951). We report information about the chromosome number and morphology, C-banding patterns, and localization of ribosomal DNA clusters and telomeric (TTAGG)n repeats. Among these species, only S. paramonovi had an ancestral Pamphagidae karyotype (2n=18+X0♂; FN=19♂). The karyotypes of the remaining species differed from the ancestral karyotypes. The karyotypes of E. bicoloripes and E. saussurei, despite having the same chromosome number (2n=18+X0♂) had certain biarmed chromosomes (FN=20♂ and FN=34♂ respectively). The karyotypes of T. escalerai and Tropidauchen sp. consisted of eight pairs of acrocentric autosomes, one submetacentric neo-X chromosome and one acrocentric neo-Y chromosome in males (2n=16+neo-X neo-Y♂). The karyotype of P. citimus consisted of seven pairs of acrocentric autosomes, submetacentric the neo-X1 and neo-Y and acrocentric the neo-X2 chromosomes (2n=14+neo-X1 neo-X2 neo-Y♂). Comparative analysis of the localization and size of C-positive regions, the position of ribosomal clusters and the telomeric DNA motif in the chromosomes of the species studied, revealed early unknown features of their karyotype evolution. The data obtained has allowed us to hypothesize that the origin and early phase of evolution of the neo-Xneo-Y♂ sex chromosome in the subfamily Pamphaginae, are linked to the Iranian highlands.

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Research Article Tue, 10 Nov 2020 22:57:43 +0200
DNA-barcoding and a new data about the karyotype of Myotis petax (Chiroptera, Vespertilionidae) in the Russian Far East https://compcytogen.pensoft.net/article/54955/ Comparative Cytogenetics 14(4): 483-500

DOI: 10.3897/CompCytogen.v14.i4.54955

Authors: Uliana V. Gorobeyko, Irina V. Kartavtseva, Irina N. Sheremetyeva, Denis V. Kazakov, Valentin Yu. Guskov

Abstract: The DNA-barcoding and chromosomal study of the eastern water bat, Myotis petax Hollister, 1912, from the earlier unexplored localities in the Russian Far East are carried out. The COI barcoding obtained for 18 from a total of 19 individuals captured in five localities in the Russian Far East showed the low nucleotide variability with the prevalence of the central, the most abundant haplotype. The chromosomal characteristics of eight M. petax specimens (2n = 44, NFa = 52) in the Russian Far East are clarified. The number and localization of NOR in karyotype of M. petax is described at the first time and differ from distributional patterns of NOR in the sibling species M. daubentonii Kuhl, 1819 that can be used as diagnostic feature. The considerable intraspecific variability in the distribution of heterochromatin material revealed is not typical of the genus Myotis, but it has been found in other species of the family Vespertilionidae.

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Research Article Mon, 19 Oct 2020 11:08:31 +0300
The highly rearranged karyotype of the hangingfly Bittacus sinicus (Mecoptera, Bittacidae): the lowest chromosome number in the order https://compcytogen.pensoft.net/article/53533/ Comparative Cytogenetics 14(3): 353-367

DOI: 10.3897/CompCytogen.v14i3.53533

Authors: Ying Miao, Bao-Zhen Hua

Abstract: Cytogenetic features of the hangingfly Bittacus sinicus Issiki, 1931 were investigated for the first time using C-banding and DAPI (4',6-diamidino-2-phenylindole) staining. The karyotype analyses show that the male B. sinicus possesses the lowest chromosome number (2n = 15) ever observed in Mecoptera, and an almost symmetric karyotype with MCA (Mean Centromeric Asymmetry) of 12.55 and CVCL (Coefficient of Variation of Chromosome Length) of 19.78. The chromosomes are either metacentric or submetacentric with their sizes decreasing gradually. Both the C-banding and DAPI+ patterns detect intermediate heterochromatin on the pachytene bivalents of B. sinicus, definitely different from the heterochromatic segment at one bivalent terminal of other bittacids studied previously. The male meiosis of B. sinicus is chiasmate with two chiasmata in metacentric bivalents and one in the submetacentric bivalent. The sex determination mechanism is X0(♂), which is likely plesiomorphic in Bittacidae. Two alternative scenarios of karyotype origin and evolution in Bittacus Latreille, 1805 are discussed.

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Research Article Thu, 30 Jul 2020 11:05:05 +0300
Chromosomal and reproductive features of some Oriental and Australasian scale insects (Homoptera, Coccinea) https://compcytogen.pensoft.net/article/53367/ Comparative Cytogenetics 14(3): 339-352

DOI: 10.3897/CompCytogen.v14i3.53367

Authors: Ilya A. Gavrilov-Zimin

Abstract: Fourteen species of scale insects from the families Margarodidae s.l., Pseudococcidae, Eriococcidae, and Coccidae were investigated for the first time in respect to karyotypes, genetic systems, modes of reproduction and general anatomy of the female reproductive system. One of the studied species, Steatococcus samaraius Morrison, 1927, showed hermaphroditic reproduction of the female-like specimens, the other species demonstrated bisexual reproduction with a peculiar “Lecanoid” heterochromatinization of the paternal set of chromosomes in male embryos or thelytocous parthenogenesis. Antonina parazonata Williams, 2004 and Saccharolecanium krugeri (Zehntner, 1897) are recorded here for the first time from Thailand, Antonina vietnamensis Williams, 2004 and Geococcus satellitum Williams, 2004 – for the first time from Laos.

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Research Article Mon, 20 Jul 2020 14:39:37 +0300
Induction and evaluation of colchitetraploids of two species of Tinospora Miers, 1851 https://compcytogen.pensoft.net/article/33394/ Comparative Cytogenetics 14(2): 211-229

DOI: 10.3897/CompCytogen.v14i2.33394

Authors: Rakesh Kr. Thakur, Vijay Rani Rajpal, Satyawada Rama Rao, Apekshita Singh, Lata Joshi, Pankaj Kaushal, Soom Nath Raina

Abstract: Autotetraploidy, both natural and/or induced, has potential for genetic improvement of various crop species including that of medicinal importance. Tinospora cordifolia (Willdenow, 1806) Miers, 1851 ex Hooker et Thomson, 1855 and T. sinensis (Loureiro, 1790) Merrill, 1934 are two diploid species, which are dioecious, deciduous and climbing shrubs with high medicinal importance. Among the three methods used for induction of polyploidy by colchicine treatment, it was cotton swab method which successfully induced the polyploidy in both species. The morphological and cytogenetical features of the synthetic tetraploids were compared with their diploid counterparts. The tetraploids were morphologically distinct from diploid plants. They exhibited larger organs, such as stem, leaves, inflorescence, fruits, flowers and seeds. The tetraploids were characterized by the presence of low quadrivalent frequency and high bivalent average. Unequal distribution of chromosomes at anaphase I was found in 60% cells. The present study provides important information on the superiority of autotetraploids as compared to diploid counterparts in both species.

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Research Article Wed, 20 May 2020 14:32:19 +0300
Cloning and preliminary verification of telomere-associated sequences in upland cotton https://compcytogen.pensoft.net/article/49391/ Comparative Cytogenetics 14(2): 183-195

DOI: 10.3897/CompCytogen.v14i2.49391

Authors: Yuling Liu, Zhen Liu, Yangyang Wei, Yanjun Wang, Jiaran Shuang, Renhai Peng

Abstract: Telomeres are structures enriched in repetitive sequences at the end of chromosomes. In this study, using the telomere primer AA(CCCTAAA)3CCC for the single primer PCR, two DNA sequences were obtained from Gossypium hirsutum (Linnaeus, 1753) accession (acc.) TM-1. Sequence analysis showed that the two obtained sequences were all rich in A/T base, which was consistent with the characteristic of the telomere-associated sequence (TAS). They were designated as GhTAS1 and GhTAS2 respectively. GhTAS1 is 489 bp long, with 57.6% of A/T, and GhTAS2 is 539 bp long, with 63.9% of A/T. Fluorescence in situ hybridization results showed that both of the cloned TASs were located at the ends of the partial chromosomes of G. hirsutum, with the strong signals, which further confirmed that GhTAS1 and GhTAS2 were telomere-associated sequences including highly tandemly repetitive sequences. Results of blast against the assembled genome of G. hirsutum showed that GhTAS sequences may be missed on some assembled chromosomes. The results provide important evidence for the evaluation of the integrity of assembled chromosome end sequences, and will also contribute to the further perfection of the draft genomes of cotton.

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Research Article Mon, 6 Apr 2020 16:48:14 +0300
New data on karyotype, spermatogenesis and ovarian trophocyte ploidy in three aquatic bug species of the families Naucoridae, Notonectidae, and Belostomatidae (Nepomorpha, Heteroptera) https://compcytogen.pensoft.net/article/48709/ Comparative Cytogenetics 14(1): 139-156

DOI: 10.3897/CompCytogen.v14i1.48709

Authors: Desislava Stoianova, Nikolay Simov, Manh Quang Vu, Duc Minh Nguyen, Snejana Grozeva

Abstract: We report the karyotype, some aspects of spermatogenesis, and ovarian trophocytes ploidy in three aquatic bug species: Ilyocoris cimicoides (Linnaeus, 1758), Notonecta glauca Linnaeus, 1758, and Diplonychus rusticus Fabricius, 1871 from previously unexplored regions – South Europe (Bulgaria) and Southeast Asia (Vietnam). Our results add considerable support for the published karyotype data for these species. In I. cimicoides, we observed achiasmate male meiosis – the first report of achiasmy for the family Naucoridae. More comprehensive cytogenetic studies in other species of the Naucoridae are required to elucidate the role of achiasmy as a character in the systematics of the family. Our observations on the association between phases of spermatogenesis and developmental stages in I. cimicoides and N. glauca differ from the previously published data. In these species, we assume that the spermatogenesis phases are not strongly associated with certain developmental stages. For further cytogenetic studies (on the Balkan Peninsula), we recommend July as the most appropriate month for collection of I. cimicoides and N. glauca. In the ovaries of both species, we studied the level of ploidy in metaphase and interphase trophocytes. In I. cimicoides, diploid and tetraploid metaphase trophocytes were found. Heteropycnotic elements, observed in interphase trophocytes of this species, represented the X chromosomes. It allowed us to determine the trophocytes ploidy at interphase (2n was repeated up to 16 times). The situation with N. glauca was different. The metaphase trophocytes were diploid and we were not able to determine the ploidy of interphase trophocytes since such conspicuous heteropycnotic elements were not found. The scarce data available suggest a tendency for a low level of trophocyte ploidy in the basal infraorders (Nepomorpha and Gerromorpha) and for a high level in the more advanced Pentatomomorpha. Data about this character in species from other infraorders are needed to confirm that tendency.

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Research Article Thu, 5 Mar 2020 17:12:41 +0200
Cytogenetic and pollen identification of genus Gagnepainia (Zingiberaceae) in Thailand https://compcytogen.pensoft.net/article/47346/ Comparative Cytogenetics 14(1): 11-25

DOI: 10.3897/CompCytogen.v14i1.47346

Authors: Paramet Moonkaew, Nattapon Nopporncharoenkul, Thaya Jenjittikul, Puangpaka Umpunjun

Abstract: Gagnepainia godefroyi K. Schumann, 1904 and G. harmandii K. Schumann, 1904 belong to the genus Gagnepainia K. Schumann, 1904 of the Ginger family. They have the potential to be developed as medicinal and attractive ornamental plants. To date, the knowledge on the cytological and reproductive aspects of Gagnepainia have not been publicly available. Therefore, the aims of this research are to investigate the cytogenetic and pollen characters of Gagnepainia species using light, fluorescence, and scanning electron microscopes. The regular meiotic figures of 15 bivalents are found in both species and presented for the first time. These evidences indicate that Gagnepainia is diploid and contains 2n = 2x = 30 with basic number of x = 15. The mean nuclear DNA contents range from 1.986 pg in Gagnepainia sp., 2.090 pg in G. godefroyi to 2.195 pg in G. harmandii. Pollens of all species are monad, inaperturate, prolate with bilateral symmetry, and thick wall with fossulate exine sculpturing. The pollen size of G. harmandii (74.506 ± 5.075 μm, 56.082 ± 6.459 μm) is significantly larger than that of G. godefroyi (59.968 ± 3.484 μm, 45.439 ± 2.870 μm). Both 2C DNA content and pollen size are the effective characteristics for species discrimination. The reproductive evidence of high meiotic stability and normal pollen production indicate that both Gagnepainia species have high fertility and seed productivity, which are in accordance with the broad distribution. The present study provides good cytogenetic and pollen characters not only for plant identification, but also plant fertility assessment through plant genetic resource management and improvement of Gagnepainia.

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Research Article Mon, 13 Jan 2020 13:26:26 +0200
Triploidy in Chinese parthenogenetic Helophorus orientalis Motschulsky, 1860, further data on parthenogenetic H. brevipalpis Bedel, 1881 and a brief discussion of parthenogenesis in Hydrophiloidea (Coleoptera) https://compcytogen.pensoft.net/article/47656/ Comparative Cytogenetics 14(1): 1-10

DOI: 10.3897/CompCytogen.v14i1.47656

Authors: Robert B. Angus, Fenglong Jia

Abstract: The chromosomes of triploid parthenogenetic Helophorus orientalis Motschulsky, 1860 are described from material from two localities in Heilongjiang, China. 3n = 33. All the chromosomes have clear centromeric C-bands, and in the longest chromosome one replicate appears to be consistently longer than the other two. The chromosomes of additional triploid parthenogenetic H. brevipalpis Bedel, 1881, from Spain and Italy, are described. In one Italian population one of the autosomes is represented by only two replicates and another appears more evenly metacentric than in material from Spain and the other Italian locality. Parthenogenetic and bisexual specimens of H. orientalis are illustrated, along with Pleistocene fossil material. Parthenogenetic H. brevipalpis is also illustrated. Parthenogenesis in Hydrophiloidea is discussed. It appears to be rare and, in all cases has been detected by chromosomal analysis of populations in which males are unexpectedly scarce. Parthenogenesis is suspected in Helophorus aquila Angus et al., 2014, from northern Qinghai (China), which should be verified in further studies.

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Research Article Mon, 13 Jan 2020 13:09:37 +0200
Cytogenetic and molecular characteristics of rye genome in octoploid triticale (× Triticosecale Wittmack) https://compcytogen.pensoft.net/article/39576/ Comparative Cytogenetics 13(4): 423-434

DOI: 10.3897/CompCytogen.v13i4.39576

Authors: Elena V. Evtushenko, Yulia A. Lipikhina, Petr I. Stepochkin, Alexander V. Vershinin

Abstract: Alloploidization resulting from remote (interspecific or intergeneric) hybridization is one of the main factors in plant evolution, leading to the formation of new species. Triticale (× Triticosecale Wittmack, 1889) is the first artificial species created by crossing wheat (Triticum spp.) and rye (Secale cereale Linnaeus, 1753) and has a great potential as a grain and forage crop. Remote hybridization is a stress factor that causes a rapid reorganization of the parental genomes in hybrid progeny (“genomic shock”) and is accompanied by abnormalities in the chromosome set of hybrids. The formation of the hybrid genome and its subsequent stabilization are directly related to the normalization of meiosis and the correct chromosome segregation. The aim of this work was to cytogenetically characterize triticale (× Triticosecale rimpaui Wittmack, 1899, AABBDDRR) obtained by crossing Triticum aestivum Linnaeus, 1753. Triple Dirk D × Secale cereale L. Korotkostebel’naya 69 in F3–F6 generations of hybrids, and to trace the process of genetic stabilization of hybrid genomes. Also, a comparative analysis of the nucleotide sequences of the centromeric histone CENH3 genes was performed in wheat-rye allopolyploids of various ploidy as well as their parental forms. In the hybrid genomes of octoploid triticale an increased expression of the rye CENH3 variants was detected. The octoploid triticale plants contain complete chromosome sets of the parental subgenomes maintaining the chromosome balance and meiotic stability. For three generations the percentage of aneuploids in the progeny of such plants has been gradually decreasing, and they maintain a complete set of the paternal rye chromosomes. However, the emergence of hexaploid and new aneuploid plants in F5 and F6 generations indicates that stabilization of the hybrid genome is not complete yet. This conclusion was confirmed by the analysis of morphological features in hybrid plants: the progeny of one plant having the whole chromosome sets of parental subgenomes showed significant morphological variations in awn length and spike density. Thus, we expect that the results of our karyotyping of octoploid triticales obtained by crossing hexaploid wheat to diploid rye supplemented by comparative analysis of CENH3 sequences will be applicable to targeted breeding of stable octo- and hexaploid hybrids.

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Research Article Mon, 16 Dec 2019 12:31:14 +0200
Description of the karyotype of Sphyracephala detrahens (Diptera, Diopsidae) https://compcytogen.pensoft.net/article/47302/ Comparative Cytogenetics 13(4): 383-388

DOI: 10.3897/CompCytogen.v13i4.47302

Authors: Ayumi Kudo

Abstract: The eye stalks in Diopsidae (Bilberg, 1820) have been widely examined, but the evolutionary origin of this unique trait remains unclear. Thus, further studies of Sphiracephala (Say, 1828), the extant genus forming a basal branch of Diopsinae, are needed. The present study aimed to identify the karyotype of Sphyracephala detrahens (Walker, 1860) with conventional Giemsa staining. Cytogenetic analysis revealed a diploid number of 2n = 10 including two pairs of metacentric chromosomes, a pair of telocentric chromosomes, a pair of dot-like chromosomes, and a pair of sex chromosomes in S. detrahens. The congener Sphyracephala brevicornis (Say, 1817) has been reported to have the same diploid number, 2n = 10, but different chromosome formula. These results demonstrate that chromosome rearrangements often occur in the genus Sphyracephala.

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Short Communication Tue, 3 Dec 2019 14:18:21 +0200
Karyotype of Polyommatus (Agrodiaetus) eriwanensis Forster, 1960 and taxonomic position of P. (A.) interjectus de Lesse, 1960 (Lepidoptera, Lycaenidae) https://compcytogen.pensoft.net/article/46897/ Comparative Cytogenetics 13(4): 359-366

DOI: 10.3897/CompCytogen.v13i4.46897

Authors: Vladimir Lukhtanov, Alexander Dantchenko

Abstract: The karyotype of Polyommatus (Agrodiaetus) eriwanensis Forster, 1960 from the type locality (“Eriwan” [Yerevan, Armenia]) and other localities in Armenia was investigated. The number of chromosomal elements (bivalents+ multivalents) observed in male meiosis I was found to vary from 29 to 34. In individuals with n = 34, all observed elements were represented by bivalents. In other specimens, heterozygosity for different number of chromosomal fusions resulted in multivalent formation at MI stage and consequently in a lower number of recognizable chromosomal elements. We show that all karyotype peculiarities of P. (A.) interjectus de Lesse, 1960 (n = 29–32) from Turkey are similar to those in A. eriwanensis. The butterflies of these taxa have allopatric distribution and can be considered as conspecific.

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Short Communication Tue, 12 Nov 2019 18:20:43 +0200
Karyotype characteristics, chromosomal polymorphism and gene COI sequences of Chironomus heteropilicornis Wülker, 1996 (Diptera, Chironomidae) from the South Caucasus https://compcytogen.pensoft.net/article/35572/ Comparative Cytogenetics 13(4): 339-357

DOI: 10.3897/CompCytogen.v13i4.35572

Authors: Mukhamed Kh. Karmokov

Abstract: The study presents data on the karyotype characteristics, features of chromosomal polymorphism and the gene COI sequences of Chironomus heteropilicornis Wülker, 1996 (Diptera, Chironomidae) from the South Caucasus. We found 8 banding sequences in the Caucasian population. Overall, The Caucasian population of the species can be characterized as having a low level of polymorphism. We found one new banding sequence hpiA2 in the banding sequence pool of Ch. heteropilicornis. We observed inversion polymorphism only in the arm F. The dendrogram of genetic distances by Nei criteria (1972) shows a clear separation of the Caucasian population from populations of Siberia. At the same time, the distance between populations of Siberia and the population of South Caucasus (0.379–0.445) almost reach the mean distance (0.474 ± 0.314) between subspecies (Gunderina 2001). Due to this, we can assume that the population of South Caucasus separated from Siberian populations at the level of subspecies. Constructed on data for COI gene sequences the phylogenetic tree estimated by the Bayesian inference shows that the sequences of Ch. heteropilicornis from the South Caucasus form a separate line in the general branch of Ch. heteropilicornis sequences. At the same time, calculated K2P genetic distances between Ch. heteropilicornis sequences from Norway and Caucasus (2.0–2.2%) do not exceed the 3% threshold for the genus Chironomus.

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Research Article Thu, 31 Oct 2019 19:07:13 +0200
Molecular cytogenetic characterization and phylogenetic analysis of four Miscanthus species (Poaceae) https://compcytogen.pensoft.net/article/35346/ Comparative Cytogenetics 13(3): 211-230

DOI: 10.3897/CompCytogen.v13i3.35346

Authors: Yan-Mei Tang, Liang Xiao, Yasir Iqbal, Jian-Feng Liao, Long-Qian Xiao, Zi-Li Yi, Chao-Wen She

Abstract: Chromosomes of four Miscanthus (Andersson, 1855) species including M. sinensis (Andersson, 1855), M. floridulus (Schumann & Lauterb, 1901), M. sacchariflorus (Hackel, 1882) and M. lutarioriparius (Chen & Renvoize, 2005) were analyzed using sequentially combined PI and DAPI (CPD) staining and fluorescence in situ hybridization (FISH) with 45S rDNA probe. To elucidate the phylogenetic relationship among the four Miscanthus species, the homology of repetitive sequences among the four species was analyzed by comparative genomic in situ hybridization (cGISH). Subsequently four Miscanthus species were clustered based on the internal transcribed spacer (ITS) of 45S rDNA. Molecular cytogenetic karyotypes of the four Miscanthus species were established for the first time using chromosome measurements, fluorochrome bands and 45S rDNA FISH signals, which will provide a cytogenetic tool for the identification of these four species. All the four have the karyotype formula of Miscanthus species, which is 2n = 2x = 38 = 34m(2SAT) + 4sm, and one pair of 45S rDNA sites. The latter were shown as strong red bands by CPD staining. A non-rDNA CPD band emerged in M. floridulus and some blue DAPI bands appeared in M. sinensis and M. floridulus. The hybridization signals of M. floridulus genomic DNA to the chromosomes of M. sinensis and M. lutarioriparius genomic DNA to the chromosomes of M. sacchariflorus were stronger and more evenly distributed than other combinations. Molecular phylogenetic trees showed that M. sinensis and M. floridulus were closest relatives, and M. sacchariflorus and M. lutarioriparius were also closely related. These findings were consistent with the phylogenetic relationships inferred from the cGISH patterns.

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Research Article Fri, 9 Aug 2019 15:48:34 +0300
Rapid chromosomal evolution in enigmatic mammal with XX in both sexes, the Alay mole vole Ellobius alaicus Vorontsov et al., 1969 (Mammalia, Rodentia) https://compcytogen.pensoft.net/article/34224/ Comparative Cytogenetics 13(2): 147-177

DOI: 10.3897/CompCytogen.v13i2.34224

Authors: Irina Bakloushinskaya, Elena A. Lyapunova, Abdusattor S. Saidov, Svetlana A. Romanenko, Patricia C.M. O’Brien, Natalia A. Serdyukova, Malcolm A. Ferguson-Smith, Sergey N. Matveevsky, Aleksey S. Bogdanov

Abstract: Evolutionary history and taxonomic position for cryptic species may be clarified by using molecular and cytogenetic methods. The subterranean rodent, the Alay mole vole Ellobius alaicus Vorontsov et al., 1969 is one of three sibling species constituting the subgenus Ellobius Fischer, 1814, all of which lost the Y chromosome and obtained isomorphic XX sex chromosomes in both males and females. E. alaicus is evaluated by IUCN as a data deficient species because their distribution, biology, and genetics are almost unknown. We revealed specific karyotypic variability (2n = 52–48) in E. alaicus due to different Robertsonian translocations (Rbs). Two variants of hybrids (2n = 53, different Rbs) with E. tancrei Blasius, 1884 were found at the Northern slopes of the Alay Ridge and in the Naryn district, Kyrgyzstan. We described the sudden change in chromosome numbers from 2n = 50 to 48 and specific karyotype structure for mole voles, which inhabit the entrance to the Alay Valley (Tajikistan), and revealed their affiliation as E. alaicus by cytochrome b and fragments of nuclear XIST and Rspo1 genes sequencing. To date, it is possible to expand the range of E. alaicus from the Alay Valley (South Kyrgyzstan) up to the Ferghana Ridge and the Naryn Basin, Tien Shan at the north-east and to the Pamir-Alay Mountains (Tajikistan) at the west. The closeness of E. tancrei and E. alaicus is supported, whereas specific chromosome and molecular changes, as well as geographic distribution, verified the species status for E. alaicus. The case of Ellobius species accented an unevenness in rates of chromosome and nucleotide changes along with morphological similarity, which is emblematic for cryptic species.

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Data Paper Thu, 20 Jun 2019 22:46:52 +0300
Identification of sex chromosomes in Eremias velox (Lacertidae, Reptilia) using lampbrush chromosome analysis https://compcytogen.pensoft.net/article/34116/ Comparative Cytogenetics 13(2): 121-132

DOI: 10.3897/CompCytogen.v13i2.34116

Authors: Artem P. Lisachov, Svetlana A. Galkina, Alsu F. Saifitdinova, Svetlana A. Romanenko, Daria A. Andreyushkova, Vladimir A. Trifonov, Pavel M. Borodin

Abstract: Reptiles are good objects for studying the evolution of sex determination, since they have different sex determination systems in different lineages. Lacertid lizards have been long-known for possessing ZZ/ZW type sex chromosomes. However, due to morphological uniformity of lacertid chromosomes, the Z chromosome has been only putatively cytologically identified. We used lampbrush chromosome (LBC) analysis and FISH with a W-specific probe in Eremias velox (Pallas, 1771) to unequivocally identify the ZW bivalent and investigate its meiotic behavior. The heterochromatic W chromosome is decondensed at the lampbrush stage, indicating active transcription, contrast with the highly condensed condition of the lampbrush W chromosomes in birds. We identified the Z chromosome by its chiasmatic association with the W chromosome as chromosome XIII of the 19 chromosomes in the LBC karyotype. Our findings agree with previous genetic and genomic studies, which suggested that the lacertid Z chromosome should be one of the smaller macrochromosomes.

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Research Article Tue, 14 May 2019 13:07:10 +0300
Analysis of chromosome karyotype and genome size in echiuran Urechis unicinctus Drasche, 1880 (Polychaeta, Urechidae) https://compcytogen.pensoft.net/article/31448/ Comparative Cytogenetics 13(1): 75-85

DOI: 10.3897/CompCytogen.v13i1.31448

Authors: Zhenkui Qin, Xueyu Li, Danwen Liu, Qing Wang, Li Lu, Zhifeng Zhang

Abstract: Karyotype and genome size are two primary cytogenetic characteristics of species, which are of great significance to the study of cytogenetics, taxonomy, phylogenesis, evolution as well as molecular biology. However, this basic cytogenetic information in echiurans is lacking. Therefore, we analyzed characteristics of karyotype and genome size in the echiuran worm Urechis unicinctus Drasche, 1880. In this study, coelomic cells of U. unicinctus were used for analyzing the genome size by a flow cytometry with chicken erythrocytes as DNA standard, and the 2C DNA content was determined to be 1.85 pg, which was corresponded to the genome size of 904.58 Mbp approximately. Furthermore, trochophores of U. unicinctus were dissociated and cells were utilized for preparing the chromosomes stained with DAPI, and the karyotype was determined as 2n = 30 (10m + 6sm + 6st + 8t), FN=52. Our data provided the basic cytogenetic information of U. unicinctus, which could be utilized in taxonomic study and whole-genome sequencing in future.

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Research Article Wed, 13 Mar 2019 21:41:02 +0200
New insights into the karyotype evolution of the genus Gampsocleis (Orthoptera, Tettigoniinae, Gampsocleidini) https://compcytogen.pensoft.net/article/29574/ Comparative Cytogenetics 12(4): 529-538

DOI: 10.3897/CompCytogen.v12i4.29574

Authors: Maciej Kociński, Beata Grzywacz, Dragan Chobanov, Elżbieta Warchałowska-Śliwa

Abstract: Five species belonging to the genus Gampsocleis Fieber, 1852 were analyzed using fluorescence in situ hybridization (FISH) with 18S rDNA and telomeric probes, as well as C-banding, DAPI/CMA3 staining and silver impregnation. The studied species showed two distinct karyotypes, with 2n = 31 (male) and 2n = 23 (male) chromosomes. The drastic reduction in chromosome number observed in the latter case suggests multiple translocations and fusions as the main responsible that occurred during chromosome evolution. Two groups of rDNA distribution were found in Gampsocleis representatives analyzed. Group 1, with a single large rDNA cluster on the medium-sized autosome found in four species, carried in the haploid karyotype. Group 2, represented only by G. abbreviata, was characterized by the presence of two rDNA signals. TTAGG telomeric repeats were found at the ends of chromosome arms as expected. The rDNA clusters coincided with active NORs and GC-rich segments.

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Research Article Wed, 19 Dec 2018 12:42:24 +0200
Cytogenetic studies in three octopods, Octopus minor, Amphioctopus fangsiao, and Cistopus chinensis from the coast of China https://compcytogen.pensoft.net/article/25462/ Comparative Cytogenetics 12(3): 373-386

DOI: 10.3897/CompCytogen.v12i3.25462

Authors: Jin-hai Wang, Xiao-dong Zheng

Abstract: To provide markers to identify chromosomes in the genome of octopods, chromosomes of three octopus species were subjected to NOR/C-banding. In addition, we examined their genome size (C value) to submit it to the Animal Genome Size Database. Silver staining revealed that the number of Ag-nucleoli was 2 (Octopus minor (Sasaki, 1920)), 2 (Amphioctopus fangsiao (d’Orbigny, 1839)) and 1 (Cistopus chinensis Zheng et al., 2012), respectively, and the number of Ag-nucleoli visible was the same as that of Ag-NORs on metaphase plates in the same species. In all analyzed metaphases, Ag-NORs were mainly located terminally on the long arms of chromosomes 3 (3rd) of O. minor and on the short arms of chromosomes 4 (4th) of A. fangsiao, whereas only one of the chromosomes 23 (23rd) was found Ag-NORs of C. chinensis. C-bands were localized predominantly in the centromeric regions of chromosomes in the three species, while other conspicuous stable C-bands were observed in terminal regions, including the Ag-NORs. That means these three chromosome pairs (3rd, 4th and 23rd) could be considered species-specific cytogenetic markers. The mean C values of O. minor, A. fangsiao and C. chinensis were 7.81±0.39 pg (0.070 pg per unit length), 8.31±0.18 pg (0.068 pg per unit length) and 5.29±0.10 pg (0.038 pg per unit length), respectively, and results showed that C values of the three species were not proportional to the relative length of the chromosomes. These cytogenetic characteristics will provide more theoretical foundation for further researches on chromosome evolution in octopods.

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Research Article Tue, 4 Sep 2018 18:11:10 +0300
First cytogenetic analysis of lesser gymnures (Mammalia, Galericidae, Hylomys) from Vietnam https://compcytogen.pensoft.net/article/27207/ Comparative Cytogenetics 12(3): 361-372

DOI: 10.3897/CompCytogen.v12i3.27207

Authors: Svetlana V. Pavlova, Larisa S. Biltueva, Svetlana A. Romanenko, Natalya A. Lemskaya, Anton V. Shchinov, Alexei V. Abramov, Viatcheslav V. Rozhnov

Abstract: Gymnures are an ancient group of small insectivorous mammals and are characterized by a controversial taxonomic status and the lack of a description of karyotypes for certain species. In this study, conventional cytogenetic techniques (Giemsa, CBG- and GTG-banding, Ag-NOR), CMA3-DAPI staining, and fluorescent in situ hybridization (FISH) with telomeric DNA probes were used to examine for the first time the karyotypes of lesser gymnures of group Hylomys suillus Müller, 1840 from northern and southern Vietnam. All studied specimens had karyotypes with 2n=48, NFa=64. C-positive heterochromatic blocks existed in centromeric regions of 7 bi-armed autosomes and the submetacentric X chromosome. The Y chromosome is a C-positive and dot-like. The nucleolus organizer regions resided terminally on the short arms of 2 small bi-armed pairs. Positive signals at the telomeres of all chromosomes were revealed by FISH. CMA3-positive blocks were localized on the telomeric and pericentric regions of most bi-armed and acrocentric chromosomes. Despite the large genetic distances between Hylomys Müller, 1840, lesser gymnures from H. suillus-group from northern and southern Vietnam have similar karyotypic characteristics.

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Research Article Thu, 23 Aug 2018 15:54:43 +0300
23rd International Colloquium on Animal Cytogenetics and Genomics (23 ICACG) June 9–12, 2018, Saint-Petersburg, Russia https://compcytogen.pensoft.net/article/27748/ Comparative Cytogenetics 12(3): 299-360

DOI: 10.3897/CompCytogen.v12i3.27748

Authors: Svetlana Galkina, Maria Vishnevskaya

Abstract: In memory of Ingemar Gustavsson 23rd International Colloquium on Animal Cytogenetics and Genomics (23 ICACG) took place in June 9–12, 2018 in Saint-Petersburg, Russia. Organized biennially, the Colloquium runs from 1970. From its very start this meeting is associated with the name of Ingemar Gustavsson to whom we dedicated the Colloquium 2018. The long and productive career of Ingemar Gustavsson had focused on chromosomes and their fundamental role in animal physiology, fertility, health and production in the context of agriculture and veterinary medicine. His meticulous analysis of breeding data performed back in 1964–69 resulted in the unequivocal identification of an association between heterozygosity for the 1/29 translocation in Swedish cattle and reduction in the fertility of the breed. Eventually, the argument in favor of selective elimination of bulls carrying the translocation from the breeding programs prevailed and the field of modern veterinary cytogenetics was established. Participants from fourteen different countries attended the 23 ICACG in Russia, the country having long lasting traditions in cytogenetics and the Scientific schools of N.K. Koltzov, S.S. Chetverikov and A.S. Serebrovsky, geneticists who made important conceptual contributions to studies of chromosomes and genes, population genetics and evolutionary theory as early as in the beginning of the XX-th century. All the abstracts received were subdivided between plenary and seven scientific sessions covering the issues in evolutionary and comparative cytogenetics, cytogenetics and genomes of domestic animals, meiosis studies, particular chromosome analyses, clinical cytogenetics, karyotypes and genomes of vertebrate and invertebrate animals, chromatin studies. In the abstract text below each presentation is marked with a capital letter: „L” stands for lectures, „O” for oral presentations and „P” for poster presentations. We gratefully acknowledge the support from the Saint-Petersburg Association of Scientists and Scholars (SPbSU), Veterinary Genetics Center ZOOGEN, Russian Foundation for Basic Research (RFBR), VEUK, Helicon, Axioma BIO, BioVitrum, Sartorius, DIA-M companies. The current collected abstracts comprise written contributions of the presentations during the 23 ICACG and were edited by Svetlana Galkina and Maria Vishnevskaya. The next Colloquium – 24 ICACG – will be held at the University of Kent in Canterbury (UK) in 2020. Please, cite abstracts as follows: Gall JG (2018) Giant chromosomes and deep sequences: what the amphibian egg tells us about transcription. In: Galkina SA, Vishnevskaya MS, Mikhailova EI (Eds) 23rd Inernational Colloquium on Animal Cytogenetics and Genomics (23rdICACG), June 9–12, 2018, St Petersburg, Russia. Comparative Cytogenetics 12(3): p–p. https://doi.org/10.3897/CompCytogen.v12i3.27748

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Forum Paper Thu, 16 Aug 2018 15:53:12 +0300
Karyotype characteristics and chromosomal polymorphism of Chironomus “annularius” sensu Strenzke (1959) (Diptera, Chironomidae) from the Caucasus region https://compcytogen.pensoft.net/article/25832/ Comparative Cytogenetics 12(3): 267-284

DOI: 10.3897/CompCytogen.v12i3.25832

Authors: Mukhamed Kh. Karmokov

Abstract: The study presents data on the karyotype characteristics and features of chromosomal polymorphism of Chironomus “annularius” sensu Strenzke (1959) (Diptera, Chironomidae) from three populations of the Caucasus region (South and Central Caucasus, and Eastern Ciscaucasia). We found 17 banding sequences in the Caucasian populations. We observed inversion polymorphism in almost all chromosome arms except for arm G. The genetic distances between all the studied populations of Ch. “annularius” were calculated using Nei criteria (1972). In spite of relative geographic proximity, the genetic distances between populations of the Caucasus are quite large, and they do not form a single cluster of Caucasian populations. The population of the South Caucasus goes to the European cluster, the population of the Central Caucasus goes to the Asian cluster and the population of Eastern Ciscaucasia does not belong to any of the outlined clusters. Principal component analysis (PCA) shows a similar picture. Two of the Caucasian populations do not follow Hardy-Weinberg expectation, there being a marked deficiency of heterozygotes in arms A, B and C, arguably, due to negative selection of heterozygotes or founder effect. All the obtained data are indicative of the complex genetic structure of Caucasian populations of Ch. “annularius” and total complexity microevolution processes occurring in the Caucasus region.

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Research Article Mon, 30 Jul 2018 13:57:58 +0300
Mysterious meiotic behavior of autopolyploid and allopolyploid maize https://compcytogen.pensoft.net/article/24907/ Comparative Cytogenetics 12(2): 247-265

DOI: 10.3897/CompCytogen.v12i2.24907

Authors: Muhammad Zafar Iqbal, Mingjun Cheng, Yanli Zhao, Xiaodong Wen, Ping Zhang, Lei Zhang, Asif Ali, Tingzhao Rong, Qi Lin Tang

Abstract: This study was aimed to investigate the stability of chromosomes during meiosis in autopolyploid and allopolyploid maize, as well as to determine an association of chromosomes between maize (Zea mays ssp. mays Linnaeus, 1753) and Z. perennis (Hitchcock, 1922) Reeves & Mangelsdor, 1942, by producing a series of autopolyploid and allopolyploid maize hybrids. The intra-genomic and inter-genomic meiotic pairings in these polyploids were quantified and compared using dual-color genomic in-situ hybridization. The results demonstrated higher level of chromosome stability in allopolyploid maize during meiosis as compared to autopolyploid maize. In addition, the meiotic behavior of Z. perennis was relatively more stable as compared to the allopolyploid maize. Moreover, ten chromosomes of "A” subgenome in maize were homologous to twenty chromosomes of Z. perennis genome with a higher pairing frequency and little evolutionary differentiation. At the same time, little evolutionary differentiation has been shown by chromosomes of "A” subgenome in maize, while chromosomes of "B” subgenome, had a lower pairing frequency and higher evolutionary differentiation. Furthermore, 5IM + 5IIPP + 5IIIMPP and 5IIMM + 5IIPP + 5IVMMPP were observed in allotriploids and allotetraploids respectively, whereas homoeologous chromosomes were found between the "A” and "B” genome of maize and Z. perennis.

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Research Article Fri, 20 Jul 2018 22:47:35 +0300
The revision of chromosome III (EF) mapping in Chironomus plumosus (Linnaeus, 1758) group (Diptera, Chironomidae) https://compcytogen.pensoft.net/article/23327/ Comparative Cytogenetics 12(2): 201-222

DOI: 10.3897/CompCytogen.v12i2.23327

Authors: Veronika V. Golygina, Iya I. Kiknadze

Abstract: A revision of mapping of main and alternative banding sequences in chromosome III (EF) has been made for 14 species of the Chironomus plumosus group. In total, new versions of mapping are presented for 18 banding sequences of arm E and 18 banding sequences of arm F. A new way of tracing the origins of banding sequences in chromosome III of the Ch. plumosus group in comparison with basic banding sequences of the genus Chironomus is suggested. The presented data indicate that h’pluE2 in arm E and p’borF2 in arm F are the closest to banding sequences of Ch. piger Strenzke, 1959 and thus should be considered the most ancient among banding sequences of chromosome III in the Ch. plumosus group. Phylogenetic relationships of banding sequences of chromosome III are discussed.

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Research Article Wed, 6 Jun 2018 19:46:56 +0300
Genomic in situ hybridization in interspecific hybrids of scallops (Bivalvia, Pectinidae) and localization of the satellite DNA Cf303, and the vertebrate telomeric sequences (TTAGGG)n on chromosomes of scallop Chlamys farreri (Jones & Preston, 1904) https://compcytogen.pensoft.net/article/14995/ Comparative Cytogenetics 12(1): 83-95

DOI: 10.3897/CompCytogen.v12i1.14995

Authors: Liping Hu, Liming Jiang, Ke Bi, Huan Liao, Zujing Yang, Xiaoting Huang, Zhenming Bao

Abstract: Mitotic chromosome preparations of the interspecific hybrids Chlamys farreri (Jones & Preston, 1904) × Patinopecten yessoensis (Jay, 1857), C. farreri × Argopecten irradians (Lamarck, 1819) and C. farreri × Mimachlamys nobilis (Reeve, 1852) were used to compare two different scallop genomes in a single slide. Although genomic in situ hybridization (GISH) using genomic DNA from each scallop species as probe painted mitotic chromosomes of the interspecific hybrids, the painting results were not uniform; instead it showed species-specific distribution patterns of fluorescent signals among the chromosomes. The most prominent GISH-bands were mainly located at centromeric or telomeric regions of scallop chromosomes. In order to illustrate the sequence constitution of the GISH-bands, the satellite Cf303 sequences of C. farreri and the vertebrate telomeric (TTAGGG)n sequences were used to map mitotic chromosomes of C. farreri by fluorescence in situ hybridization (FISH). The results indicated that the GISH-banding pattern presented by the chromosomes of C. farreri is mainly due to the distribution of the satellite Cf303 DNA, therefore suggesting that the GISH-banding patterns found in the other three scallops could also be the result of the chromosomal distribution of other species-specific satellite DNAs.

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Research Article Tue, 13 Mar 2018 11:44:49 +0200
“European” race-specific metacentrics in East Siberian common shrews (Sorex araneus): a description of two new chromosomal races, Irkutsk and Zima https://compcytogen.pensoft.net/article/19800/ Comparative Cytogenetics 11(4): 797-806

DOI: 10.3897/CompCytogen.v11i4.19800

Authors: Svetlana V. Pavlova, Sergei A. Borisov, Alexander F. Timoshenko, Boris I. Sheftel

Abstract: Karyotype studies of common shrews in the vicinity of Lake Baikal (Irkutsk Region, Eastern Siberia) resulted in the description of two new chromosomal races of Sorex araneus Linnaeus, 1758 (Lypotyphla, Mammalia), additional to 5 races formerly found in Siberia. In the karyotypes of 12 specimens from 3 locations, the polymorphism of metacentric and acrocentric chromosomes of the Robertsonian type was recorded and two distinct groups of karyotypes interpreted as the chromosomal races were revealed. They are geographically distant and described under the racial names Irkutsk (Ir) and Zima (Zi). Karyotypes of both races were characterized by species-specific (the same for all 74 races known so far) metacentric autosomes af, bc, tu and jl, and the typical sex chromosome system – XX/XY1Y2. The race-specific arm chromosome combinations include three metacentrics and four acrocentrics in the Irkutsk race (gk, hi, nq, m, o, p, r) and four metacentrics and two acrocentrics in the Zima race (gm, hi, ko, nq, p, r). Within the races, individuals with polymorphic chromosomes were detected (g/m, k/o, n/q, p/r). The presence of the specific metacentric gk allowed us to include the Irkutsk race into the Siberian Karyotypic Group (SKG), distributed in surrounding regions. The Zima race karyotype contained two metacentrics, gm and ko, which have been never found in the Siberian part of the species range, but appear as the common feature of chromosomal races belonging to the West European Karyotypic Group (WEKG). Moreover, the metacentrics of that karyotype are almost identical to the Åkarp race (except the heterozygous pair p/r) locally found in the southern Sweden. One of two Siberian races described here for the first time, the Zima race, occurs in an area considerably distant from Europe and shares the common metacentrics (gm, hi, ko) with races included in WEKG. This fact may support a hypothesis of independent formation of identical arm chromosome combinations due to occurrence of the same centric fusions in different parts of the species range.

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Research Article Fri, 24 Nov 2017 17:05:14 +0200
A new butterfly species from south Russia revealed through chromosomal and molecular analysis of the Polyommatus (Agrodiaetus) damonides complex (Lepidoptera, Lycaenidae) https://compcytogen.pensoft.net/article/20072/ Comparative Cytogenetics 11(4): 769-795

DOI: 10.3897/CompCytogen.v11i4.20072

Authors: Vladimir A. Lukhtanov, Alexander V. Dantchenko

Abstract: Finding a new species is a rare event in easy-to-see and well-studied organisms like butterflies, especially if they inhabit well-explored areas such as the Western Palaearctic. However, even in this region, gaps in taxonomic knowledge still exist and here we report such a discovery. Using a combined analysis of chromosomal and molecular markers we demonstrate that Polyommatus blue populations from Daghestan (South Russia), previously identified as P. aserbeidschanus, represent in fact a new species which is described here as P. australorossicus sp. n. We also show that the enigmatic Polyommatus damonides described as a form of Polyommatus damone and later considered as an entity similar to P. poseidon or P. ninae is conspecific with a taxon previously known as P. elbursicus. As a result of our study, we propose several taxonomic changes within the P. damonides species complex and suggest the following new combinations: P. damonides elbursicus Forster, 1956, comb. n. and P. damonides gilanensis Eckweiler, 2002, comb. n.

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Research Article Fri, 24 Nov 2017 14:50:45 +0200
Chromosomal identification of cryptic species sharing their DNA barcodes: Polyommatus (Agrodiaetus) antidolus and P. (A.) morgani in Iran (Lepidoptera, Lycaenidae) https://compcytogen.pensoft.net/article/20876/ Comparative Cytogenetics 11(4): 759-768

DOI: 10.3897/compcytogen.v11i4.20876

Authors: Vladimir A. Lukhtanov, Nazar A. Shapoval

Abstract: DNA barcoding has been suggested as a universal tool for molecular species identification; however, it cannot be applied in cases when morphologically similar species share their DNA barcodes due to the common ancestry or mitochondrial introgression. Here we analyze the karyotype of Polyommatus (Agrodiaetus) morgani (Le Cerf, 1909) from the region of its type locality in the southern Zagros Mountains in Iran, provide first chromosomal evidence for P. (A.) antidolus (Rebel, 1901) in Iran and demonstrate that these two species can be easily identified through analysis of their karyotypes whereas they share their mitochondrial barcodes.

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Short Communication Tue, 21 Nov 2017 14:03:11 +0200
Dual mechanism of chromatin remodeling in the common shrew sex trivalent (XY 1Y 2) https://compcytogen.pensoft.net/article/13870/ Comparative Cytogenetics 11(4): 727-745

DOI: 10.3897/compcytogen.v11i4.13870

Authors: Sergey N. Matveevsky, Svetlana V. Pavlova, Maret M. Atsaeva, Jeremy B. Searle, Oxana L. Kolomiets

Abstract: Here we focus on the XY1Y2 condition in male common shrew Sorex araneus Linnaeus, 1758, applying electron microscopy and immunocytochemistry for a comprehensive analysis of structure, synapsis and behaviour of the sex trivalent in pachytene spermatocytes. The pachytene sex trivalent consists of three distinct parts: short and long synaptic SC fragments (between the X and Y1 and between the X and Y2, respectively) and a long asynaptic region of the X in-between. Chromatin inactivation was revealed in the XY1 synaptic region, the asynaptic region of the X and a very small asynaptic part of the Y2. This inactive part of the sex trivalent, that we named the ‘head’, forms a typical sex body and is located at the periphery of the meiotic nucleus at mid pachytene. The second part or ‘tail’, a long region of synapsis between the X and Y2 chromosomes, is directed from the periphery into the nucleus. Based on the distribution patterns of four proteins involved in chromatin inactivation, we propose a model of meiotic silencing in shrew sex chromosomes. Thus, we conclude that pachytene sex chromosomes are structurally and functionally two different chromatin domains with specific nuclear topology: the peripheral inactivated ‘true’ sex chromosome regions (part of the X and the Y1) and more centrally located transcriptionally active autosomal segments (part of the X and the Y2).

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Research Article Fri, 3 Nov 2017 13:41:40 +0200
Meiotic behaviour and its implication on species inter-relationship in the genus Curcuma (Linnaeus, 1753) (Zingiberaceae) https://compcytogen.pensoft.net/article/14726/ Comparative Cytogenetics 11(4): 691-702

DOI: 10.3897/compcytogen.v11i4.14726

Authors: Judith Mary Lamo, Satyawada Rama Rao

Abstract: In this paper, detailed meiotic analysis was investigated in seven species of Curcuma (Linnaeus, 1753) which can contribute significantly to our understanding about species inter-relationship, speciation and evolution. The species were divided into two groups viz., Group I having 2n = 42 (C. comosa Roxburgh, 1810, C. haritha Mangaly & M.Sabu, 1993, C. mangga Valeton & Zijp, 1917, and C. motana Roxburgh, 1800) and Group II with 2n = 63 (C. caesia Roxburgh, 1810, C. longa Linnaeus, 1753 and C. sylvatica Valeton, 1918). Both groups display varying degree of chromosome associations. Group I species showed the prevalence of bivalents, however occasional quadrivalents besides univalents were also encountered. About 48% of the PMCs analyzed in C. mangga showed 21 bivalents (II) meiotic configurations, 32% in C. comosa and 16% in C. haritha. Group II species as expected showed the presence of trivalents besides bivalents, univalents and quadrivalents. About 32% of the PMCs analyzed at MI in C. sylvatica showed 21 trivalents (III) meiotic configurations, 24% in C. longa and 8% in C. caesia. Overall, low frequency of multivalent associations as compared to bivalents indicates that Curcuma is an allopolyploid complex. Moreover, x = 21 is too high a basic number, therefore, we suggest that the genus Curcuma has evolved by hybridization of species with different chromosome numbers of 2n = 24 and 18, resulting in a dibasic amphidiploid species.

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Research Article Tue, 24 Oct 2017 13:35:38 +0300
Contribution to the cytogenetics of Kuwaniini scale insects (Homoptera, Coccinea, Margarodidae s.l.) https://compcytogen.pensoft.net/article/20168/ Comparative Cytogenetics 11(4): 659-663

DOI: 10.3897/CompCytogen.v11i4.20168

Authors: Ilya Gavrilov-Zimin

Abstract: Jansenus burgeri Foldi, 1997 (Margarodidae s.l., Xylococcinae, Kuwaniini) was studied cytogenetically for the first time. It was shown that the species reproduces bisexually, displays XX/X(0) sex chromosome system and 2n=6/5 (female/male) including two pairs of long autosomes and a pair of shorter X-chromosomes in female. The chromosome complement, adult female morphology and the life cycle of J. burgeri are illustrated. The cytogenetic data are in fact the first ones for Kuwaniini scale insects, because Kuwania oligostigma De Lotto, 1959 briefly cytogenetically studied by Hughes-Schrader (1963), in my opinion, may be excluded from the genus Kuwania Cockerell, 1903 and the tribe Kuwaniini, since this species shows aberrant morphological characters, specifically the total absence of abdominal spiracles and the presence of tubular ducts.

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Short Communication Thu, 14 Sep 2017 10:54:59 +0300
Chromosomal constitutions of five wheat – Elytrigia elongata partial amphiploids as revealed by GISH, multicolor GISH and FISH https://compcytogen.pensoft.net/article/11883/ Comparative Cytogenetics 11(3): 525-540

DOI: 10.3897/CompCytogen.v11i3.11883

Authors: Fang He, Yuhai Wang, Yinguang Bao, Yingxue Ma, Xin Wang, Xingfeng Li, Honggang Wang

Abstract: A combination of meiotic pairing analysis and in situ hybridization (genomic in situ hybridization [GISH], multicolor GISH [mcGISH] and fluorescence in situ hybridization [FISH]) of five Triticum aestivum (Linnaeus, 1753) - Elytrigia elongata (Podpěra, 1902) (2n = 10x = 70) amphiploids was employed to investigate the genomic constitution and relationships between wheat and alien chromosomes. GISH, multicolor GISH and FISH patterns of mitotic chromosomes indicate that the genomic constitution of the five partial amphiploids (XY693, XY7430, SN19, SN20 and SN122) are 14A + 12B + 14D + 8Js + 8J, 12A + 16B + 14D + 2St + 8Js + 2J + 2 W-E, 14A + 14B + 14D + 4St + 8Js, 14A + 14B + 14D + 2St + 10Js + 2J, and 14A + 14B + 14D + 2St + 8Js + 4J, respectively. Analysis of meiotic chromosome pairing in the F1 hybrids between these five partial amphiploids suggests that SN20 and SN122 are the most closely related amphiploids and are somewhat related with XY693 and XY7430. However, the alien chromosome constitutions of SN19 differed from the other four amphiploids. In addition, a new pairing between wheat and E. elongata chromosomes was distinguished in some cells of the hybrids SN19 × XY7430, SN20 × XY7430 and SN122 × XY7430.

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Research Article Thu, 3 Aug 2017 11:07:41 +0300
Diversification of the P genome among Agropyron Gaertn. (Poaceae) species detected by FISH https://compcytogen.pensoft.net/article/13124/ Comparative Cytogenetics 11(3): 495-509

DOI: 10.3897/CompCytogen.v11i3.13124

Authors: Yan Zhao, Jihong Xie, Quanwen Dou, Junjie Wang, Zhong Zhang

Abstract: The genomes of five Agropyron Gaertner, 1770 species were characterized using all potential di- or trinucleotide simple sequence repeat (SSR) motifs and four satellite DNA repeats as fluorescence in situ hybridization (FISH) probes. The sites of 5S and 45S rDNA were relatively conserved among the diploid and tetraploid species. A number of sites for the dinucleotide SSRs AC, AG, and pSc119.2 was detected in all investigated species except A. mongolicum Keng, 1938. Several different trinucleotide SSRs were identified in different tetraploid species. All Agropyron species were suggested to include the basic P genome, although genome differentiation was still observed. The P genome of A. mongolicum was distinct from that of the diploid A. cristatum (Linnaeus, 1753) Gaertner, 1770. and other tetraploid species, with no hybridizations for AC, AG, or pSc119.2 observed. This finding supports designation of the P genomes of A. cristatum and A. mongolicum as Pc and Pm, respectively. An exceptional 5S rDNA site revealed in one set of homoeologous chromosomes strongly supports the allopolyploid origin of A. desertorum (Fischer ex Link, 1821) Schultes, 1824. However, the diploid donors to A. desertorum need further investigation. Similarly, the unique FISH pattern of a pair of 5S rDNA-carrying chromosomes was indicative of a potential allopolyploid origin for A. fragile (Roth, 1800) Candargy, 1984. The conserved distribution of 5S and 45S rDNA suggests A. cristatum (4x) and A. michnoi Roshevitz, 1929 are closely related. Two forms of B chromosomes were identified among individuals A. mongolicum and A. desertorum plants.

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Research Article Thu, 3 Aug 2017 11:04:59 +0300
Comparison of the genetic relationship between nine Cephalopod species based on cluster analysis of karyotype evolutionary distance https://compcytogen.pensoft.net/article/12752/ Comparative Cytogenetics 11(3): 477-494

DOI: 10.3897/compcytogen.v11i3.12752

Authors: Jin-hai Wang, Xiao-dong Zheng

Abstract: Karyotype analysis was carried out on gill cells of three species of octopods using a conventional air-drying method. The karyotype results showed that all the three species have the same diploid chromosome number, 2n=60, but with different karyograms as 2n=38M+6SM+8ST+8T, FN (fundamental number)=104 (Cistopus chinensis Zheng et al., 2012), 2n=42M+6SM+4ST+8T, FN=108 (Octopus minor (Sasaki, 1920)) and 2n=32M+16SM+12T, FN=108 (Amphioctopus fangsiao (d’Orbigny, 1839–1841)). These findings were combined with data from earlier studies to infer the genetic relationships between nine species via cluster analysis using the karyotype evolutionary distance (De) and resemblance-near coefficient (λ). The resulting tree revealed a clear distinction between different families and orders which was substantially consistent with molecular phylogenies. The smallest intraspecific evolutionary distance (De=0.2013, 0.2399) and largest resemblance-near coefficient (λ=0.8184, 0.7871) appeared between O. minor and C. chinensis, and Sepia esculenta Hoyle, 1885 and S. lycidas Gray, 1849, respectively, indicating that these species have the closest relationship. The largest evolutionary gap appeared between species with complicated karyotypes and species with simple karyotypes. Cluster analysis of De and λ provides information to supplement traditional taxonomy and molecular systematics, and it would serve as an important auxiliary for routine phylogenetic study.

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Research Article Tue, 25 Jul 2017 10:46:50 +0300
Karyological characterization and identification of four repetitive element groups (the 18S – 28S rRNA gene, telomeric sequences, microsatellite repeat motifs, Rex retroelements) of the Asian swamp eel (Monopterus albus) https://compcytogen.pensoft.net/article/11739/ Comparative Cytogenetics 11(3): 435-462

DOI: 10.3897/compcytogen.v11i3.11739

Authors: Aorarat Suntronpong, Watcharaporn Thapana, Panupon Twilprawat, Ornjira Prakhongcheep, Suthasinee Somyong, Narongrit Muangmai, Surin Peyachoknagul, Kornsorn Srikulnath

Abstract: Among teleost fishes, Asian swamp eel (Monopterus albus Zuiew, 1793) possesses the lowest chromosome number, 2n = 24. To characterize the chromosome constitution and investigate the genome organization of repetitive sequences in M. albus, karyotyping and chromosome mapping were performed with the 18S – 28S rRNA gene, telomeric repeats, microsatellite repeat motifs, and Rex retroelements. The 18S – 28S rRNA genes were observed to the pericentromeric region of chromosome 4 at the same position with large propidium iodide and C-positive bands, suggesting that the molecular structure of the pericentromeric regions of chromosome 4 has evolved in a concerted manner with amplification of the 18S – 28S rRNA genes. (TTAGGG)n sequences were found at the telomeric ends of all chromosomes. Eight of 19 microsatellite repeat motifs were dispersedly mapped on different chromosomes suggesting the independent amplification of microsatellite repeat motifs in M. albus. Monopterus albus Rex1 (MALRex1) was observed at interstitial sites of all chromosomes and in the pericentromeric regions of most chromosomes whereas MALRex3 was scattered and localized to all chromosomes and MALRex6 to several chromosomes. This suggests that these retroelements were independently amplified or lost in M. albus. Among MALRexs (MALRex1, MALRex3, and MALRex6), MALRex6 showed higher interspecific sequence divergences from other teleost species in comparison. This suggests that the divergence of Rex6 sequences of M. albus might have occurred a relatively long time ago.

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Research Article Tue, 27 Jun 2017 16:16:57 +0300
Cytogenetic maps of homoeologous chromosomes A h01 and D h01 and their integration with the genome assembly in Gossypium hirsutum https://compcytogen.pensoft.net/article/12824/ Comparative Cytogenetics 11(2): 405-420

DOI: 10.3897/CompCytogen.v11i2.12824

Authors: Yuling Liu, Zhen Liu, Renhai Peng, Yuhong Wang, Zhongli Zhou, Xiaoyan Cai, Xingxing Wang, Zhenmei Zhang, Kunbo Wang, Fang Liu

Abstract: Cytogenetic maps of Gossypium hirsutum (Linnaeus, 1753) homoeologous chromosomes Ah01 and Dh01 were constructed by fluorescence in situ hybridization (FISH), using eleven homoeologous-chromosomes-shared bacterial artificial chromosomes (BACs) clones and one chromosome-specific BAC clone respectively. We compared the cytogenetic maps with the genetic linkage and draft genome assembly maps based on a standardized map unit, relative map position (RMP), which allowed a global view of the relationship of genetic and physical distances along each chromosome, and assembly quality of the draft genome assembly map. By integration of cytogenetic maps with sequence maps of the two chromosomes (Ah01 and Dh01), we inferred the locations of two scaffolds and speculated that some homologous sequences belonging to homoeologous chromosomes were removed as repetitiveness during the sequence assembly. The result offers molecular tools for cotton genomics research and also provides valuable information for the improvement of the draft genome assembly.

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Research Article Mon, 19 Jun 2017 16:13:22 +0300
Study of male–mediated gene flow across a hybrid zone in the common shrew (Sorex araneus) using Y chromosome https://compcytogen.pensoft.net/article/13494/ Comparative Cytogenetics 11(2): 421-430

DOI: 10.3897/CompCytogen.v11i2.13494

Authors: Andrei V. Polyakov, Viktor V. Panov

Abstract: Despite many studies, the impact of chromosome rearrangements on gene flow between chromosome races of the common shrew (Sorex araneus Linnaeus, 1758) remains unclear. Interracial hybrids form meiotic chromosome complexes that are associated with reduced fertility. Nevertheless comprehensive investigations of autosomal and mitochondrial markers revealed weak or no barrier to gene flow between chromosomally divergent populations. In a narrow zone of contact between the Novosibirsk and Tomsk races hybrids are produced with extraordinarily complex configurations at meiosis I. Microsatellite markers have not revealed any barrier to gene flow, but the phenotypic differentiation between races is greater than may be expected if gene flow was unrestricted. To explore this contradiction we analyzed the distribution of the Y chromosome SNP markers within this hybrid zone. The Y chromosome variants in combination with race specific autosome complements allow backcrosses to be distinguished and their proportion among individuals within the hybrid zone to be evaluated. The balanced ratio of the Y variants observed among the pure race individuals as well as backcrosses reveals no male mediated barrier to gene flow. The impact of reproductive unfitness of backcrosses on gene flow is discussed as a possible mechanism of the preservation of race-specific morphology within the hybrid zone.

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Research Article Mon, 19 Jun 2017 16:12:23 +0300
B chromosome in Plantago lagopus Linnaeus, 1753 shows preferential transmission and accumulation through unusual processes https://compcytogen.pensoft.net/article/11779/ Comparative Cytogenetics 11(2): 375-392

DOI: 10.3897/CompCytogen.v11i2.11779

Authors: Manoj K. Dhar, Gurmeet Kour, Sanjana Kaul

Abstract: Plantago lagopus is a diploid (2n = 2x =12) weed belonging to family Plantaginaceae. We reported a novel B chromosome in this species composed of 5S and 45S ribosomal DNA and other repetitive elements. In the present work, presence of B chromosome(s) was confirmed through FISH on root tip and pollen mother cells. Several experiments were done to determine the transmission of B chromosome through male and female sex tracks. Progenies derived from the reciprocal crosses between plants with (1B) and without (0B) B chromosomes were studied. The frequency of B chromosome bearing plants was significantly higher than expected, in the progeny of 1B female × 0B male. Thus, the B chromosome seems to have preferential transmission through the female sex track, which may be due to meiotic drive. One of the most intriguing aspects of the present study was the recovery of plants having more chromosomes than the standard complement of 12 chromosomes. Such plants were isolated from the progenies of B chromosome carrying plants. The origin of these plants can be explained on the basis of a two step process; formation of unreduced gametes in 1B plants and fusion of unreduced gametes with the normal gametes or other unreduced gametes. Several molecular techniques were used which unequivocally confirmed similar genetic constitution of 1B (parent) and plants with higher number of chromosomes.

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Research Article Mon, 22 May 2017 19:03:52 +0300
A new species of Melitaea from Israel, with notes on taxonomy, cytogenetics, phylogeography and interspecific hybridization in the Melitaea persea complex (Lepidoptera, Nymphalidae) https://compcytogen.pensoft.net/article/12370/ Comparative Cytogenetics 11(2): 325-357

DOI: 10.3897/CompCytogen.v11i2.12370

Authors: Vladimir A. Lukhtanov

Abstract: Specimens with intermediate morphology are often considered to be the result of ongoing interspecific hybridization; however, this conclusion is difficult to prove without analysis of chromosomal and/or molecular markers. In the butterfly genus Melitaea, such an intermediacy can be detected in male genitalia, and is more or less regularly observed in localities where two closely related, presumably parental species are found in sympatry. Here I analyze a high altitude Melitaea population from Mt. Hermon in north Israel and show that its male genitalia are clearly differentiated from those found in phenotypically similar M. persea and M. didyma, but in some aspects intermediate between them. This hybrid-like population is unique because, although M. didyma is present on Mt. Hermon, the true, low-altitude M. persea has never been reported from Israel. Cytogenetic analysis revealed no apomorphic chromosomal characters to distinguish the Mt. Hermon population from other known taxa of the M. persea and M. didyma species groups. At the same time, DNA barcode-based phylogeographic study showed that this population is ancient. It was estimated to originate 1–1.6 million years ago in the Levantine refugium from a common ancestor with M. persea. Generally, the data obtained are incompatible with interpretation of the studied population as a taxon conspecific with M. persea or M. didyma, or a swarm of recent hybrids between M. persea and M. didyma, although the possibility of ancient homoploid hybrid speciation cannot be ruled out. I also argue that the name Melitaea montium assigned to butterflies from north Lebanon cannot be applied to the studied taxon from Mt. Hermon. Here I describe this morphologically and ecologically distinct entity as a new species Melitaea acentria sp. n., and compare it with other taxa of the M. persea complex.

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Research Article Fri, 5 May 2017 12:55:46 +0300
Further studies on Boreonectes Angus, 2010, with a molecular phylogeny of the Palaearctic species of the genus https://compcytogen.pensoft.net/article/11980/ Comparative Cytogenetics 11(2): 189-201

DOI: 10.3897/CompCytogen.v11i2.11980

Authors: Robert B. Angus, Ignacio Ribera, Fenglong Jia

Abstract: Karyotypes are given for Boreonectes emmerichi (Falkenström, 1936) from its type locality at Kangding, China, and for B. alpestris (Dutton & Angus, 2007) from the St Gotthard and San Bernardino passes in the Swiss Alps. A phylogeny based on sequence data from a combination of mitochondrial and nuclear genes recovered western Palaearctic species of Boreonectes as monophyletic with strong support. Boreonectes emmerichi was placed as sister to the north American forms of B. griseostriatus (De Geer, 1774), although with low support. The diversity of Palaearctic species of the B. griseostriatus species group is discussed.

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Research Article Wed, 22 Mar 2017 12:10:58 +0200
Variation in genome size and karyotype among closely related aphid parasitoids (Hymenoptera, Aphelinidae) https://compcytogen.pensoft.net/article/10872/ Comparative Cytogenetics 11(1): 97-117

DOI: 10.3897/CompCytogen.v11i1.10872

Authors: Vladimir E. Gokhman, Kristen L. Kuhn, James B. Woolley, Keith R. Hopper

Abstract: Genome sizes were measured and determined for the karyotypes of nine species of aphid parasitoids in the genus Aphelinus Dalman,1820. Large differences in genome size and karyotype were found between Aphelinus species, which is surprising given the similarity in their morphology and life history. Genome sizes estimated from flow cytometry were larger for species in the A. mali (Haldeman, 1851) complex than those for the species in the A. daucicola Kurdjumov, 1913 and A. varipes (Förster,1841) complexes. Haploid karyotypes of the A. daucicola and A. mali complexes comprised five metacentric chromosomes of similar size, whereas those of the A. varipes complex had four chromosomes, including a larger and a smaller metacentric chromosome and two small acrocentric chromosomes or a large metacentric and three smaller acrocentric chromosomes. Total lengths of female haploid chromosome sets correlated with genome sizes estimated from flow cytometry. Phylogenetic analysis of karyotypic variation revealed a chromosomal fusion together with pericentric inversions in the common ancestor of the A. varipes complex and further pericentric inversions in the clade comprising Aphelinus kurdjumovi Mercet, 1930 and Aphelinus hordei Kurdjumov, 1913. Fluorescence in situ hybridization with a 28S ribosomal DNA probe revealed a single site on chromosomes of the haploid karyotype of Aphelinus coreae Hopper & Woolley, 2012. The differences in genome size and total chromosome length between species complexes matched the phylogenetic divergence between them.

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Research Article Thu, 23 Feb 2017 12:44:51 +0200
Distribution, karyomorphology, and morphology of Aspidistra subrotata (Asparagaceae) at different ploidy levels in limestone areas of Asia https://compcytogen.pensoft.net/article/9803/ Comparative Cytogenetics 11(1): 1-13

DOI: 10.3897/CompCytogen.v11i1.9803

Authors: Jian-she Chen, Qi Gao, Hao Zhou, Yu-song Huang, Mikinori Ogisu, Ming Cao

Abstract: Aspidistra subrotata Y. Wan & C.C. Huang, 1987 is considered for the first time as a widespread polyploidy complex in the genus Aspidistra Ker Gawler, 1823 from limestone areas of Asia. The chromosome number of the tetraploid is 2n = 76 and the karyotype is formulated as 2n = 44 m + 8 sm + 24 st, while the chromosome number of the diploid is 2n = 38 and the karyotype formula 2n = 22 m + 4 sm + 12 st. In our studies, diploids occupy broader geographical and environmental niche spaces than tetraploids. Although the leaf-shape of A. subrotata varies quantitatively between and within diploid and/or tetraploid population(s), no obvious discontinuity in the width of leaf has been observed. The tetraploid plants may be distinguished from the diploid plants by their rigid petioles as well as thick deep green lamina. A. subrotata is therefore an interesting material to explore the formation and the evolutionary dynamics of a natural polyploid complex from limestone areas of the tropical regions.

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Research Article Mon, 9 Jan 2017 18:56:00 +0200
Chromosomal and mitochondrial diversity in Melitaea didyma complex (Lepidoptera, Nymphalidae): eleven deeply diverged DNA barcode groups in one non-monophyletic species? https://compcytogen.pensoft.net/article/11069/ Comparative Cytogenetics 10(4): 697-717

DOI: 10.3897/CompCytogen.v10i4.11069

Authors: Elena A. Pazhenkova, Vladimir A. Lukhtanov

Abstract: It is generally accepted that cases of species’ polyphyly in COI trees arising as a result of deep intraspecific divergence are negligible, and the detected cases reflect misidentifications or/and methodological errors. Here we studied the problem of species’ non-monophyly through chromosomal and molecular analysis of butterfly taxa close to Melitaea didyma (Esper, 1779) (Lepidoptera, Nymphalidae). We found absence or low interspecific chromosome number variation and presence of intraspecific variation, therefore we conclude that in this group, chromosome numbers have relatively low value as taxonomic markers. Despite low karyotype variability, the group was found to have unexpectedly high mitochondrial haplotype diversity. These haplotypes were clustered in 23 highly diverged haplogroups. Twelve of these haplogroups are associated with nine traditionally recognized and morphologically distinct species M. chitralensis Moore, 1901, M. deserticola Oberthür, 1909, M. didymoides Eversmann, 1847, M. gina Higgins, 1941, M. interrupta Colenati, 1846, M. latonigena Eversmann, 1847, M. mixta Evans, 1912, M. saxatilis Christoph, 1873 and M. sutschana Staudinger, 1892. The rest of the haplogroups (11 lineages) belong to a well-known west-palaearctic species M. didyma. The last species is particularly unusual in the haplotypes we obtained. First, it is clearly polyphyletic with respect to COI gene. Second, the differentiation in COI gene between these mostly allopatric (but in few cases sympatric) eleven lineages is extremely high (up to 7.4%), i.e. much deeper than the “standard” DNA barcode species threshold (2.7–3%). This level of divergence normally could correspond not even to different species, but to different genera. Despite this divergence, the bearers of these haplogroups were found to be morphologically indistinguishable and, most importantly, to share absolutely the same ecological niches, i.e. demonstrating the pattern which is hardly compatible with hypothesis of multiple cryptic species. Most likely such a profound irregularity in barcodes is caused by reasons other than speciation and represents an extraordinary example of intra-species barcode variability. Given the deep level of genetic differentiation between the lineages, we assume that there was a long period (up to 5.0 My) of allopatric differentiation when the lineages were separated by geographic or/and ecological barriers and evolved in late Pliocene and Pleistocene refugia of north Africa, the Iberian and Balkan Peninsulas, the Middle East and Central Asia. We discuss the refugia-within-refugia concept as a mechanism explaining the presence of additional diverged minor haplogroups within the areas of the major haplogroups. We also provide the first record of M. gina in Azerbaijan and the record of M. didyma turkestanica as a new taxon for Russia and Europe.

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Research Article Tue, 6 Dec 2016 14:01:18 +0200
Mitochondrial chromosome as a marker of animal migratory routes: DNA barcoding revealed Asian (non-African) origin of a tropical migrant butterfly Junonia orithya in south Israel https://compcytogen.pensoft.net/article/11085/ Comparative Cytogenetics 10(4): 671-677

DOI: 10.3897/CompCytogen.v10i4.11085

Authors: Vladimir A. Lukhtanov, Elena A. Pazhenkova, Asya V. Novikova

Abstract: The blue pansy Junonia orithya Linnaeus, 1758 (Lepidoptera, Nymphalidae) is widely distributed along the tropical areas of Africa, Asia and Australia. It is also known as a migrant species in the Levant. Here we record J. orithya in south Israel and provide a DNA-barcode-based evidence for its Asian (non-African) origin.

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Short Communication Thu, 1 Dec 2016 12:23:48 +0200
Karyotypic features including organizations of the 5S, 45S rDNA loci and telomeres of Scadoxus multiflorus (Amaryllidaceae) https://compcytogen.pensoft.net/article/9958/ Comparative Cytogenetics 10(4): 637-646

DOI: 10.3897/CompCytogen.v10i4.9958

Authors: Pansa Monkheang, Arunrat Chaveerach, Runglawan Sudmoon, Tawatchai Tanee

Abstract: Scadoxus multiflorus Martyn, 1795 is an ornamental plant with brilliantly colored flowers. Even though its chromosomes are rather large, there is no karyotype description reported so far. Therefore, conventional and molecular cytogenetic studies including fluorescence in situ hybridization (FISH) with 45S and 5S rDNA, and human telomere sequence (TTAGGG)n probes (Arabidopsis-type telomere probes yielded negative results) were carried out. The chromosome number is as reported previously, 2n = 18. The nine chromosome pairs include two large submetacentric, five large acrocentric, one medium acrocentric, two small metacentric and eight small submetacentric chromosomes. Hybridization sites of the 45S rDNA signals were on the short arm ends of chromosomes #1, #3 and #8, while 5S rDNA signals appeared on the long arm of chromosome 3, in one homologue as a double signal. The telomere signals were restricted to all chromosome ends. Three chromosome pairs could be newly identified, chromosome pair 3 by 5S rDNA and chromosomes #1, #3 and #8 by 45S rDNA loci. In addition to new information about rDNA locations we show that the ends of S. multiflorus chromosomes harbor human instead of Arabidopsis-type telomere sequences. Overall, the S. multiflorus karyotype presents chromosomal heteromorphy concerning size, shape and 45S and 5S rDNA positioning. As Scadoxus Rafinesque, 1838 and related species are poorly studied on chromosomal level the here presented data is important for better understanding of evolution in Amaryllidaceae.

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Research Article Tue, 22 Nov 2016 12:45:55 +0200
Chromosomal organization of repetitive DNAs in Hordeum bogdanii and H. brevisubulatum (Poaceae) https://compcytogen.pensoft.net/article/9666/ Comparative Cytogenetics 10(4): 465-481

DOI: 10.3897/CompCytogen.v10i4.9666

Authors: Quanwen Dou, Ruijuan Liu, Feng Yu

Abstract: Molecular karyotypes of H. bogdanii Wilensky, 1918 (2n = 14), and H. brevisubulatum Link, 1844 ssp. brevisubulatum (2n = 28), were characterized by physical mapping of several repetitive sequences. A total of 18 repeats, including all possible di- or trinucleotide SSR (simple sequence repeat) motifs and satellite DNAs, such as pAs1, 5S rDNA, 45S rDNA, and pSc119.2, were used as probes for fluorescence in situ hybridization on root-tip metaphase chromosomes. Except for the SSR motifs AG, AT and GC, all the repeats we examined produced detectable hybridization signals on chromosomes of both species. A detailed molecular karyotype of the I genome of H. bogdanii is described for the first time, and each repetitive sequence is physically mapped. A high degree of chromosome variation, including aneuploidy and structural changes, was observed in H. brevisubulatum. Although the distribution of repeats in the chromosomes of H. brevisubulatum is different from that of H. bogdanii, similar patterns between the two species imply that the autopolyploid origin of H. brevisubulatum is from a Hordeum species with an I genome. A comparison of the I genome and the other Hordeum genomes, H, Xa and Xu, shows that colocalization of motifs AAC, ACT and CAT and colocalization of motifs AAG and AGG are characteristic of the I genome. In addition, we discuss the evolutionary significance of repeats in the genome during genome differentiation.

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Research Article Fri, 7 Oct 2016 18:35:40 +0300
Microchromosome polymorphism in the sand lizard, Lacerta agilis Linnaeus, 1758 (Reptilia, Squamata) https://compcytogen.pensoft.net/article/7655/ Comparative Cytogenetics 10(3): 387-399

DOI: 10.3897/CompCytogen.v10i3.7655

Authors: Artem P. Lisachov, Pavel M. Borodin

Abstract: Most true lizards (Lacertidae) share a conservative karyotype, consisting of 18 pairs of macrochromosomes and one microchromosome pair. Homeologues of the microchromosome are present in other squamates and even in chickens. No structural autosomal microchromosome polymorphisms have been described previously in lizards. We found homozygous and heterozygous carriers of a microchromosome variant in a Siberian population of the sand lizard, Lacerta agilis Linnaeus, 1758. The variant microchromosome was almost twice as long as the standard one. In heterozygotes at pachytene, the microchromosomes firstly pair in proximal regions and the central part of the longer axial element undergoes foldback synapsis, then its distal region pairs with the distal region of the standard partner. At metaphase-I, the heteromorphic microchromosome bivalents have a proximal chiasma. The content of the additional segment was Ag-NOR, C-like DAPI, CMA3 negative. FISH with telomere PNA probe did not detect interstitial (TTAGGG)n sequences in the heteromorphic and any other bivalents. Both homo- and heterozygous carriers were phenotypically normal. The presence of homozygotes shows that heterozygotes are fertile. Reduction in the number of microchromosomes is a clear trend in squamate evolution, as a result of microchromosomes fusing together or with macrochromosomes. Our findings indicate that gaining additional DNA may lead to a transformation of microchromosomes into small macrochromosomes without fusion.

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Research Article Thu, 8 Sep 2016 11:46:51 +0300
Karyotype and sex chromosome differentiation in two Nalassus species (Coleoptera, Tenebrionidae) https://compcytogen.pensoft.net/article/9504/ Comparative Cytogenetics 10(3): 371-385

DOI: 10.3897/CompCytogen.v10i3.9504

Authors: Dirim Şendoğan, Nurşen Alpagut-Keskin

Abstract: Cytogenetic features of Nalassus bozdagus Nabozhenko & Keskin, 2010 and Nalassus plebejus Küster, 1850 were analysed using conventional and differential staining. Mitotic and meiotic chromosomal analysis revealed the diploid number as 2n = 20 (9+Xyp) in both species. Besides the general resemblance of two Nalassus Mulsant, 1854 karyotypes, important differences related to variations in the number of metacentric/submetacentric chromosomes, localization of highly impregnated regions which are considered as NOR and heterochromatin distribution are clearly observed. The most prominent difference between two species is found related to the X chromosome which is clearly larger in N. bozdagus and has a conspicuous secondary constriction on the long arm. As a result of silver staining, the existence of highly impregnated areas associated with Xyp of N. bozdagus in both prophase I and metaphase I, suggests that NORs are seemingly located on sex chromosomes. On the other hand, the potential NORs of N. plebejus were observed only in prophase I nuclei. With the application of fluorescence dye DAPI, the AT rich chromosome regions and Xyp which forms the parachute configuration were shown in both species.

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Research Article Fri, 2 Sep 2016 11:44:40 +0300
Rearrangement hotspots in the sex chromosome of the Palearctic black fly Simulium bergi (Diptera, Simuliidae) https://compcytogen.pensoft.net/article/8855/ Comparative Cytogenetics 10(2): 295-310

DOI: 10.3897/CompCytogen.v10i2.8855

Authors: Peter H. Adler, Alparslan Yildirim, Zuhal Onder, G. Taskin Tasci, Onder Duzlu, M. Ozkan Arslan, Arif Ciloglu, Baris Sari, Nilgun Parmaksizoglu, Abdullah Inci

Abstract: An extreme example of nonrandom rearrangements, especially inversion breaks, is described in the polytene chromosomes of the black fly Simulium bergi Rubtsov, 1956 from Armenia and Turkey. A total of 48 rearrangements was discovered, relative to the standard banding sequence for the subgenus Simulium Latreille, 1802. One rearrangement, an inversion (IIS-C) in the short arm of the second chromosome, was fixed. Six (12.5%) of the rearrangements were autosomal polymorphisms, and the remaining 41 (85.4%) were sex linked. More than 40 X- and Y-linked rearrangements, predominantly inversions, were clustered in the long arm of the second chromosome (IIL), representing about 15% of the total complement. The pattern conforms to a nonrandom model of chromosome breakage, perhaps associated with an underlying molecular mechanism.

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Research Article Thu, 30 Jun 2016 11:08:22 +0300
Chromosomal mapping of tandem repeats in the Yesso Scallop, Patinopecten yessoensis (Jay, 1857), utilizing fluorescence in situ hybridization https://compcytogen.pensoft.net/article/7391/ Comparative Cytogenetics 10(1): 157-169

DOI: 10.3897/CompCytogen.v10i1.7391

Authors: Xuan Li, Zujing Yang, Huan Liao, Zhengrui Zhang, Xiaoting Huang, Zhenmin Bao

Abstract: Construction of cytogenetic maps can provide important information for chromosome identification, chromosome evolution and genomic research. However, it hasn’t been conducted in many scallop species yet. In the present study, we attempted to map 12 fosmid clones containing tandem repeats by fluorescence in situ hybridization (FISH) in the Yesso scallop Patinopecten yessoensis (Jay, 1857). The results showed 6 fosmid clones were successfully mapped and distributed in 6 different pairs of chromosomes. Three clones were respectively assigned to a pair of metacentric chromosomes, a pair of submetacentric chromosomes and a pair of telocentric chromosomes and the remaining 3 clones showed their loci on three different pairs of subtelocentric chromosomes by co-hybridization. In summary, totally 8 pairs of chromosomes of the Yesso scallop were identified by 6 fosmid clones and two rDNA probes. Furthermore, 6 tandem repeats of 5 clones were sequenced and could be developed as chromosome specific markers for the Yesso scallop. The successful localization of fosmid clones will undoubtedly facilitate the integration of linkage groups with cytogenetic map and genomic research for the Yesso scallop.

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Research Article Mon, 21 Mar 2016 11:13:21 +0200
Identification of homogeneously staining regions by G-banding and chromosome microdissection, and FISH marker selection using human Alu sequence primers in a scleractinian coral Coelastrea aspera Verrill, 1866 (Cnidaria) https://compcytogen.pensoft.net/article/5699/ Comparative Cytogenetics 10(1): 61-75

DOI: 10.3897/CompCytogen.v10i1.5699

Authors: Takahiro Taguchi, Satoshi Kubota, Takuma Mezaki, Erika Tagami, Satoko Sekida, Shu Nakachi, Kazuo Okuda, Akira Tominaga

Abstract: Karyotype analysis was performed on the scleractinian coral Coelastrea aspera Verrill, 1866, commonly found along temperate coasts in Japan (30–35°N) and in coastal waters in the Indian and Pacific oceans. G-banding of C. aspera was successfully performed, although the banding pattern was not as clear as that in mammals. The karyogram clearly revealed that this coral had a homogeneously staining region (hsr) in chromosome 11. This hsr consisted of ribosomal RNA (rRNA) related genes, which was demonstrated by fluorescence in situ hybridization (FISH) with probes generated using 28S ribosomal DNA (rDNA) primers and those generated through chromosome microdissection. In addition, we conducted silver-stained nucleolus organizer region (Ag-NOR) analysis and found Ag depositions in the interphase nuclei but not on rRNA gene loci and hsr(s) in the mitotic stage. The hsr of this coral was observed in approximately 50% of the metaphase spreads analyzed. This may explain the diversity of coral rDNA based on the molecular study of sequence analysis. Furthermore, it was discovered that human telomere and Alu repeated sequences were present in this C. aspera. Probes derived from human Alu sequences are expected to play an important role in the classification of corals. Overall, our data can be of great value in discriminating among scleractinian coral species and understanding their genetics, including chromosomal evolution.

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Research Article Fri, 22 Jan 2016 13:41:23 +0200
Chromosomal evidence of species status and evolutionary relationships of the black fly Prosimulium petrosum (Diptera, Simuliidae) in Armenia https://compcytogen.pensoft.net/article/6551/ Comparative Cytogenetics 10(1): 33-44

DOI: 10.3897/CompCytogen.v10i1.6551

Authors: Sergey Vlasov, Maria Harutyunova, Karine Harutyunova, Peter Adler

Abstract: The karyotype of Armenian populations of the black fly Prosimulium petrosum Rubtsov, 1955 was characterized and compared with that of all other chromosomally known Palearctic members of the Prosimulium hirtipes group. Analysis of the polytene chromosomes established that Prosimulium petrosum is most closely related to European populations of Prosimulium latimucro (Enderlein, 1925) with which it shares an identical fixed chromosomal banding sequence. Its validity as a species, separate from Prosimulium latimucro, is based on its unique sex-differential sections in the expanded centromere region of chromosome I, in agreement with the unique structural configuration of the hypostomal teeth of its larvae. Prosimulium petrosum and Prosimulium latimucro, therefore, are homosequential species, demonstrating the value of a combined chromosomal and morphological approach in determining species status.

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Research Article Fri, 22 Jan 2016 12:55:01 +0200
Sex chromosome diversity in Armenian toad grasshoppers (Orthoptera, Acridoidea, Pamphagidae) https://compcytogen.pensoft.net/article/6407/ Comparative Cytogenetics 10(1): 45-59

DOI: 10.3897/CompCytogen.v10i1.6407

Authors: Alexander G. Bugrov, Ilyas E. Jetybayev, Gayane H. Karagyan, Nicolay B. Rubtsov

Abstract: Although previous cytogenetic analysis of Pamphagidae grasshoppers pointed to considerable karyotype uniformity among most of the species in the family, our study of species from Armenia has discovered other, previously unknown karyotypes, differing from the standard for Pamphagidae mainly in having unusual sets of sex chromosomes. Asiotmethis turritus (Fischer von Waldheim, 1833), Paranocaracris rubripes (Fischer von Waldheim, 1846), and Nocaracris cyanipes (Fischer von Waldheim, 1846) were found to have the karyotype 2n♂=16+neo-XY and 2n♀=16+neo-XX, the neo-X chromosome being the result of centromeric fusion of an ancient acrocentric X chromosome and a large acrocentric autosome. The karyotype of Paranothrotes opacus (Brunner von Wattenwyl, 1882) was found to be 2n♂=14+X1X2Y and 2n♀=14+X1X1X2X2., the result of an additional chromosome rearrangement involving translocation of the neo-Y and another large autosome. Furthermore, evolution of the sex chromosomes in these species has involved different variants of heterochromatinization and miniaturization of the neo-Y. The karyotype of Eremopeza festiva (Saussure, 1884), in turn, appeared to have the standard sex determination system described earlier for Pamphagidae grasshoppers, 2n♂=18+X0 and 2n♀=18+XX, but all the chromosomes of this species were found to have small second C-positive arms. Using fluorescent in situ hybridization (FISH) with 18S rDNA and telomeric (TTAGG)n DNA repeats to yield new data on the structural organization of chromosomes in the species studied, we found that for most of them, clusters of repeats homologous to 18S rDNA localize on two, three or four pairs of autosomes and on the X. In E. festiva, however, FISH with labelled 18S rDNA painted C-positive regions of all autosomes and the X chromosome; clusters of telomeric repeats localized primarily on the ends of the chromosome arms. Overall, we conclude that the different stages of neo-Y degradation revealed in the Pamphagidae species studied make the family a very promising and useful model for studying sex chromosome evolution.

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Research Article Fri, 22 Jan 2016 12:43:43 +0200
Analysis of meiotic chromosome structure and behavior in Robertsonian heterozygotes of Ellobius tancrei (Rodentia, Cricetidae): a case of monobrachial homology https://compcytogen.pensoft.net/article/5674/ Comparative Cytogenetics 9(4): 691-706

DOI: 10.3897/CompCytogen.v9i4.5674

Authors: Sergey Matveevsky, Irina Bakloushinskaya, Valentina Tambovtseva, Svetlana Romanenko, Oxana Kolomiets

Abstract: Synaptonemal complex (SC) chains were revealed in semisterile intraspecific F1 hybrids of Ellobius tancrei Blasius, 1884 (2n = 49, NF=56 and 2n=50, NF=56), heterozygous for Robertsonian (Rb) translocations. Chains were formed by Rb submetacentrics with monobrachial homology. Chromosome synapsis in spermatocytes of these hybrids was disturbed, apparently because of the problematic release of the chromosomes from the SC chains. These hybrids suffer from low fertility, and our data support the opinion that this is because a formation of Rb metacentrics with monobrachial homology within different races of the same species might be an initial event for the divergence of chromosomal forms.

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Research Article Wed, 2 Dec 2015 12:10:48 +0200
Cytogenetic description of the earthworm Drawida ghilarovi Gates, 1969 (Oligochaeta, Moniligastridae) from the southern Russian Far East https://compcytogen.pensoft.net/article/5741/ Comparative Cytogenetics 9(4): 565-577

DOI: 10.3897/CompCytogen.v9i4.5741

Authors: Alim P. Anisimov, Galina V. Roslik, Gennady N. Ganin

Abstract: Sixty-six specimens of the earthworm Drawida ghilarovi Gates, 1969 (Oligochaeta, Moniligastridae) from 15 localities of the southern Russian Far East were studied cytogenetically. We examined chromosome sets during mitosis and diakinesis as well as DNA content in the spermatogenous and somatic cell nuclei. The populations and morphs displayed no differences in karyotype and ploidy levels estimated in terms of both chromosome number and DNA mass index: n = 10, 2n = 20; c = 1.1 pg, 2c = 2.2 pg. We conclude that polyploidy as a species- or race-forming factor is not typical of these earthworms.

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Research Article Wed, 9 Sep 2015 15:16:16 +0300
Identification of new cytotypes of Valeriana jatamansi Jones, 1970 (Valerianaceae) from North-Western Himalayan region of India https://compcytogen.pensoft.net/article/5883/ Comparative Cytogenetics 9(4): 499-512

DOI: 10.3897/CompCytogen.v9i4.8875

Authors: Savita Rani, Tilak Raj Sharma, Rakesh Kapila, Rakesh Kumar Chahota

Abstract: Valeriana jatamansi, a medicinally important species of the family Valerianaceae, has been cytologically studied in different geographical areas of North-Western Himalayan region of India. The tetraploid cytotype with chromosome numbers 2n=32 is in conformity with the earlier reports of the species from different parts of the world. An octoploid cytotype (2n=64) makes a new addition for the species on a worldwide basis, whereas the diploid cytotype (2n=16) is new to India have been reported for the first time in India. These cytotypes (2n=16, 32, 64) show significant variations with respect to morphology as well as geographical distribution in the Western Indian Himalayas. Further, anomalous populations have been marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges resulting in abnormal microsporogenesis, and production of heterogeneous-sized fertile pollen grains along with reduced pollen fertility.

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Research Article Fri, 7 Aug 2015 00:00:00 +0300
Karyotype characteristics and polymorphism peculiarities of Chironomus bernensis Wülker & Klötzli, 1973 (Diptera, Chironomidae) from the Central Caucasus and Ciscaucasia https://compcytogen.pensoft.net/article/4519/ Comparative Cytogenetics 9(3): 281-297

DOI: 10.3897/CompCytogen.v9i3.4519

Authors: Mukhamed Kh. Karmokov, Natalia V. Polukonova, Olga V. Sinishkina

Abstract: Data about the karyotype characteristics, features of chromosomal polymorphism and larval morphology of populations of Chironomus bernensis Wülker & Klötzli, 1973 (Diptera, Chironomidae) from the Central Caucasus (the northern macroslope) and Ciscaucasia are presented. The characteristics of the pericentromeric regions of the long chromosomes of this species from Caucasian populations were very similar to the ones from some European populations (from Poland and Italy), but differed from Swiss and Siberian populations. In the North Caucasian populations 10 banding sequences were found: two in arms A, C, and E, and one in arms B, D, F, and G. Nine of them were already known for this species, and one, berC2, is described for the first time. Cytogenetic distances between all the studied populations of Ch. bernensis show that close geographical location of all studied populations from the Central Caucasus and Ciscaucasia is reflected in their similar cytogenetic structure, but on the other hand, that they are more closely related to populations from Europe than to populations from Western Siberia. At the same time, all studied larvae from Caucasian populations have a four-bladed premandible, instead of a two-bladed one, as in the description of Ch. bernensis from Switzerland (Wülker and Klötzli 1973, Polukonova 2005c). These peculiarities may indicate the relative isolation of the Caucasus from the viewpoint of microevolution. Further research on karyological and morphological characteristics of Chironomus bernensis from geographically distant regions is necessary as there is a possibility that the presently known species is actually polytypic and consists of several sibling species.

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Research Article Tue, 23 Jun 2015 08:56:42 +0300
Comparative analysis of karyotypes of Chironomus solitus Linevich & Erbaeva, 1971 and Chironomus anthracinus Zetterstedt, 1860 (Diptera, Chironomidae) from East Siberia https://compcytogen.pensoft.net/article/4702/ Comparative Cytogenetics 9(2): 237-248

DOI: 10.3897/CompCytogen.v9i2.4702

Authors: Valentina Proviz

Abstract: A comparative chromosome banding analysis of Chironomus solitus Linevich & Erbaeva, 1971 and Chironomus anthracinus Zetterstedt, 1860 from East Siberia (Lakes Baikal, Gusinoe, Arakhley and Irkutsk Reservoir) showed close similarity of banding sequences. Ch. solitus differs from Ch. anthracinus in one species-specific sequence of arm B. Arms C (43%) and D (30%) had inversion banding sequences previously reported in Ch. anthracinus The similarity of karyotypic features of Ch. solitus and Ch. anthracinus in combination with morphological features of larvae provide evidence in favour of including Ch. solitus in the C. anthracinus group of sibling species long with Ch. reservatus Shobanov, 1997.

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Research Article Wed, 3 Jun 2015 14:46:55 +0300
Chromosomal and molecular evidence for presence of Polyommatus (Agrodiaetus) poseidon (Lepidoptera, Lycaenidae) in Caucasus region https://compcytogen.pensoft.net/article/5020/ Comparative Cytogenetics 9(2): 249-255

DOI: 10.3897/CompCytogen.v9i2.5020

Authors: Vladimir A. Lukhtanov, Valentin V. Tikhonov

Abstract: We show how combination of chromosomal and molecular markers can be applied for proper species identification in Agrodiaetus Hübner, 1822 blue butterflies. Using this approach we provide first evidence for presence of P. (A.) poseidon (Herrich-Schäffer, [1851]) in Georgia.

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Short Communication Wed, 3 Jun 2015 11:31:25 +0300
Genomic in situ hybridization identifies parental chromosomes in hybrid scallop (Bivalvia, Pectinoida, Pectinidae) between female Chlamys farreri and male Argopecten irradians irradians https://compcytogen.pensoft.net/article/5323/ Comparative Cytogenetics 9(2): 189-200

DOI: 10.3897/CompCytogen.v9i2.8943

Authors: Xiaoting Huang, Ke Bi, Wei Lu, Shi Wang, Lingling Zhang, Zhenmin Bao

Abstract: Interspecific crossing was artificially carried out between Chlamys farreri (Jones & Preston, 1904) ♀ and Argopecten irradians irradians (Lamarck, 1819) ♂, two of the dominant cultivated scallop species in China. Genomic in situ hybridization (GISH) was used to examine the chromosome constitution and variation in hybrids at early embryonic stage. The number of chromosomes in 66.38% of the metaphases was 2n = 35 and the karyotype was 2n = 3 m + 5 sm + 16 st + 11 t. After GISH, two parental genomes were clearly distinguished in hybrids, most of which comprised 19 chromosomes derived from their female parent (C. farreri) and 16 chromosomes from their male parent (A. i. irradians). Some chromosome elimination and fragmentation was also observed in the hybrids.

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Research Article Wed, 20 May 2015 00:00:00 +0300
Further karyosystematic studies of the Boreonectes griseostriatus (De Geer) group of sibling species (Coleoptera, Dytiscidae)–characterisation of B. emmerichi (Falkenström, 1936) and additional European data https://compcytogen.pensoft.net/article/4463/ Comparative Cytogenetics 9(1): 133-144

DOI: 10.3897/CompCytogen.v9i1.4463

Authors: Robert B. Angus, Elizabeth M. Angus, Fenglong Jia, Zhen-ning Chen, Ying Zhang

Abstract: A lectotype is designated for the Tibetan species Deronectes emmerichi Falkenström, 1936 (Currently Boreonectes emmerichi (Falkenström)), and its habitus, as well as the median lobe and parameres of its aedeagus, are figured along with additional comparative material. Material of B. emmerichi from Sikkim (BMNH) represents the first record of a Boreonectes Angus, 2010 species from India. The karyotype of B. emmerichi is described as having 26 pairs of autosomes plus sex chromosomes which are X0 (♂), XX (♀). The karyotype is most like that of B. macedonicus (Géuorguiev, 1959), but with slight differences. Additional chromosomal information is given for B. griseostriatus griseostriatus (De Geer, 1774) in the French Alps, B. g. strandi (Brinck, 1943) on the Kola Peninsula, B. multilineatus (Falkenström, 1922) in the Pyrenees and B. ibericus (Dutton & Angus, 2007) in the Spanish Picos de Europa.

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Research Article Tue, 31 Mar 2015 10:36:21 +0300
Taxonomic position of several enigmatic Polyommatus (Agrodiaetus) species (Lepidoptera, Lycaenidae) from Central and Eastern Iran: insights from molecular and chromosomal data https://compcytogen.pensoft.net/article/4309/ Comparative Cytogenetics 8(4): 313-322

DOI: 10.3897/CompCytogen.v8i4.8939

Authors: Vladimir Lukhtanov, Nazar Shapoval, Alexander Dantchenko

Abstract: The species-rich subgenus Polyommatus (Agrodiaetus) has become one of the best studied groups of Palearctic blue butterflies (Lepidoptera, Lycaenidae). However, the identity and phylogenetic position of some rare taxa from Iran have remained unclear. An enigmatic, recently described Central Iranian species P. (A.) shirkuhensis ten Hagen et Eckweiler, 2001 has been considered as a taxon closely related either to P. (A.) eckweileri ten Hagen, 1998 or to P. (A.) baltazardi (de Lesse, 1962). P. (A.) baltazardi, in its turn, was treated as a taxon close to Iranian-Pakistani P. (A.) bogra Evans, 1932. Here we used a combination of molecular and chromosomal markers to show that none of these hypotheses was true. Instead, P. (A.) shirkuhensis was recovered as a member of a species group close to P. (A.) cyaneus (Staudinger, 1899). From genetically closest species, P. (A.) kermansis (de Lesse, 1962), P. (A.) cyaneus and P. (A.) sennanensis (de Lesse, 1959), it differs by the wing coloration. From morphologically similar P. (A.) mofidii (de Lesse, 1963) and P. (A.) sorkhensis Eckweiler, 2003, it differs by its chromosome number, n=21. P. (A.) bogra and P. (A.) baltazardi were found to be members of two different species groups and, thus, are not closely related.

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Research Article Tue, 9 Dec 2014 00:00:00 +0200
Karyotype, C-banding and AgNORs of two endemic leuciscine fish, Pseudophoxinus crassus (Ladiges, 1960) and P. hittitorum Freyhof & Özulug, 2010 (Teleostei, Cyprinidae) https://compcytogen.pensoft.net/article/4205/ Comparative Cytogenetics 8(4): 249-257

DOI: 10.3897/CompCytogen.v8i4.7623

Authors: Sevgi Unal, Muhammet Gaffaroglu, Muradiye Karasu Ayata, Esref Yüksel

Abstract: The genus Pseudophoxinus Bleeker, 1860 is found in a wide range of habitats in central Anatolia, but it is not well known from a cytogenetic aspect. In this study the first karyotypic description of the spring minnows Pseudophoxinus crassus (Ladiges, 1960) and P. hittitorum Freyhof & Özulug, 2010 by means of conventional methods (Giemsa staining, C-banding, silver nitrate impregnation (Ag-NORs)) was performed. Both species are endemic and have restricted distributions in Central Anatolia. P. crassus and P. hittitorum have the same diploid chromosome number, 2n = 50, patterns of distribution of constitutive heterochromatin (CH), and localization of nucleolus organizer regions (NORs), but differ in their karyotypic formulae (KFs). The C-banding technique revealed clear pericentromeric blocks of CH in many chromosomes; Ag-NORs treatment revealed consistent positive signals at the end of the short arms of a submetacentric chromosome pair, likely homologous in both species. The karyotypic differences found between these species can be used for their taxonomical study.

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Research Article Fri, 31 Oct 2014 00:00:00 +0200
Karyotypes of six spider species belonging to the families Gnaphosidae, Salticidae, Thomisidae, and Zodariidae (Araneae) from Turkey https://compcytogen.pensoft.net/article/1813/ Comparative Cytogenetics 8(2): 93-101

DOI: 10.3897/compcytogen.v8i2.6065

Authors: Zübeyde Kumbıçak, Emel Ekiz, Serdar Çiçekli

Abstract: In this study, the karyotypes of six spider species from Turkey belonging to the families Gnaphosidae, Salticidae, Thomisidae, and Zodariidae were analyzed. Male chromosomal features including diploid chromosome numbers and sex chromosome systems were determined as 2n=22, X1X20 in Drassyllus sur Tuneva & Esyunin, 2003, Nomisia exornata (C. L. Koch, 1839), and Nomisia orientalis Dalmas, 1921; 2n=28, X1X20 in Sitticus caricis (Westring, 1861); 2n=23, X0 in Xysticus gallicus Simon, 1875 and 2n=42, X1X20 in Pax islamita (Simon, 1873), respectively. The chromosome morphology of all species was acrocentric. Data obtained contribute to knowledge of the karyotype evolution of araneomorphs.

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Research Article Fri, 16 May 2014 00:00:00 +0300
A chromosomal investigation of four species of Chinese Panorpidae (Insecta, Mecoptera) https://compcytogen.pensoft.net/article/1795/ Comparative Cytogenetics 7(3): 229-239

DOI: 10.3897/compcytogen.v7i3.5500

Authors: Bo Xu, Yankai Li, Baozhen Hua

Abstract: The male adults of four species of the Chinese Panorpidae in Mecoptera were cytogenetically studied using conventional squashing procedures. The results show that their sex-chromosome system belongs to the XO type, with n = 19 + X(O) in Panorpa emarginata Cheng, 1949 and Panorpa dubia Chou & Wang, 1981, n = 23 + X(O) in Panorpa sp., and n = 20 + X(O) in Neopanorpa lui Chou & Ran, 1981. X chromosomes of these species usually appear dot-shaped in late prophase I and are easily differentiated from autosomal bivalents. Meiosis in these Panorpidae lacks typical diplotene and diakinesis. In late prophase I, pairs of homologous chromosomes remain parallel in a line and show no evidence of crossing-over. Some of them even appear as a single unit because of extremely intimate association, all with a tendency of increasing condensation. The evolutionary significance of their chromosomal differences and the achiasmatic meiosis of Panorpidae are briefly discussed.

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Research Article Mon, 23 Sep 2013 00:00:00 +0300
A new form of the mole vole Ellobius tancrei Blasius, 1884 (Mammalia, Rodentia) with the lowest chromosome number https://compcytogen.pensoft.net/article/1788/ Comparative Cytogenetics 7(2): 163-169

DOI: 10.3897/compcytogen.v7i2.5350

Authors: Irina Bakloushinskaya, Svetlana Romanenko, Natalia Serdukova, Alexander Graphodatsky, Elena Lyapunova

Abstract: The subterranean mole vole, Ellobius tancrei, with a specific variability in autosomes (2n = 31–54) and unusual sex chromosomes (XX in males and females), represents an amazing model for studying the role of chromosome changes in speciation. New materials from the upper reaches of the Surkhob River in the Pamiro-Alay mountains resulted in the discovery of a new form with 2n = 30. The application of Zoo-FISH and G-banding methods allowed the detection of 13 pairs of autosomes as Robertsonian metacentrics originated after fusions of acrocentrics of an assumed ancestral karyotype of E. tancrei with 2n = 54. The sex chromosomes (XX, in both sexes) and one pair of acrocentric autosomes are the only acrocentrics in this karyotype, and the set with 2n = 30 possesses the lowest possible chromosome number among populations of E. tancrei.

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Data Paper Tue, 11 Jun 2013 00:00:00 +0300
Heterochromatin variation among the populations of Mus terricolor Blyth, 1851 (Rodentia, Muridae) chromosome type I https://compcytogen.pensoft.net/article/1790/ Comparative Cytogenetics 7(2): 139-151

DOI: 10.3897/compcytogen.v7i2.4136

Authors: Mahua Rudra, Min Bahadur

Abstract: Twenty five to thirty specimens each from ten populations of Mus terricolor of the Terai and the Dooars regions of the Darjeeling foothills of West Bengal were cytogenetically analyzed using C-banding. Results showed intra- and inter- population variation of C-band positive heterochromatin ranging from very large blocks to minute amounts or even complete absence of heterochromatin. Large blocks of centromeric C-bands were found in Bidhan Nagar, Garidhura, Malbazar, Nagrakata and Maynaguri populations in most of the autosomes, while the rest of the populations had large blocks of C-bands on a few autosomes only. Such intra- and inter- population variation may be due to accumulation of C-positive heterochromatin, which has not got fixed homogeneously in all autosome pairs. X-chromosomes invariably possess a C-banded short arm a telomeric C-band at the distal end of the long arm in all populations. The entire Y-chromosome was C-band positive with slight population differences in staining intensity. The results suggest quantitative as well as qualitative variation of C-positive heterochromatin.

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Research Article Tue, 28 May 2013 00:00:00 +0300
Chromosomal homology of Uraeotyphlus oxyurus group of species (Amphibia, Gymnophiona, Ichthyophiidae) https://compcytogen.pensoft.net/article/1785/ Comparative Cytogenetics 7(1): 11-23

DOI: 10.3897/compcytogen.v7i1.3603

Authors: Venu Govindappa, G Venkatachalaiah

Abstract: Uraeotyphlus oxyurus (Dumeril et Bibron, 1841), U. interruptus Pillai et Ravichandran, 1999, U. narayani Seshachar, 1939 and U. menoni Annandale, 1913 were cytogenetically analysed following conventional and differential staining techniques. These species show similar karyotypes with 2n=36 (FN=58). There were no traces of species-specific features in regard to C-banding and NOR staining. The comparative study of karyotypes shows chromosomal homologies among the four species. Chromosomal data seem to support the concept that two species groups exist in the genus Uraeotyphlus.

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Research Article Mon, 18 Mar 2013 00:00:00 +0200
Comparative karyomorphological study of some Indian Cymbidium Swartz, 1799 (Cymbidieae, Orchidaceae) https://compcytogen.pensoft.net/article/1767/ Comparative Cytogenetics 6(4): 453-465

DOI: 10.3897/compcytogen.v6i4.3461

Authors: Santosh Sharma, Suman Kumaria, Pramod Tandon, Rao Rama Satyawada

Abstract: Understanding the genetic resources and diversity is very important for the breeding programs and improvement of several economically important orchids like Cymbidium. Karyomorphological studies have been carried out on seven Cymbidium species, C. aloifolium (Linnaeus, 1753), C. devonianum Paxton,1843, C. elegans Lindley, 1828, C. iridioides D. Don, 1825, C. lowianum Rchb. f.,1877, C. tigrinum Parish ex Hook. f., 1864, and C. tracyanum L. Castle,1890, most of them endangered/threatened in their natural habitat. As reported earlier, the somatic chromosome number (2n = 40) has been observed in all the seven species. Distinct inter-specific variation was recorded in the arm ratio of few homologous pairs in the complements. Symmetrical or almost symmetrical karyotypes were prevalent; however significant asymmetry was reported in C. iridioides and C. tracyanum. The significance of karyotypic variation in speciation of the genus Cymbidium has been discussed. This study provides useful chromosome landmarks and evidence about genome evolution, heteromorphic chromosomes based heterozygosity, basic chromosome number and ploidy level in the genus Cymbidium.

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Research Article Thu, 27 Dec 2012 00:00:00 +0200
A contribution to the taxonomy, cytogenetics and reproductive biology of the genus Aclerda Signoret (Homoptera, Coccinea, Aclerdidae) https://compcytogen.pensoft.net/article/1772/ Comparative Cytogenetics 6(4): 389-395

DOI: 10.3897/compcytogen.v6i4.4320

Authors: Ilya Gavrilov-Zimin

Abstract: A new species of scale insects, Aclerda pseudozoysiae sp. n., is described and illustrated. The karyotypes and some aspects of reproductive biology and cytogenetics of the new species species and Aclerda takahashii Kuwana, 1932 were studied, representing the first data for the genus Aclerda Signoret, 1874 and the family Aclerdidae as a whole. A. pseudozoysiae sp. n. has 2n=16, bisexual reproduction, and heterochromatinization of one haploid set of chromosomes in male stages of the life cycle, matching either a Lecanoid or a Comstockioid genetic system. A. takahashii demonstrates 2n=18 and unusual type of parthenogenesis with diploid and haploid embryos (inside each gravid female) without heterochromatinization. Both species are ovoviviparous; all stages of embryonic development occur inside the mother’s body.

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Short Communication Fri, 30 Nov 2012 00:00:00 +0200
The chromosomes of Tsing-Ling pika, Ochotona huangensis Matschie, 1908 (Lagomorpha, Ochotonidae) https://compcytogen.pensoft.net/article/1776/ Comparative Cytogenetics 6(4): 347-358

DOI: 10.3897/compcytogen.v6i4.3183

Authors: Alexey Vakurin, Vladimir Korablev, Xue-Long Jiang, Tat'iana Grigor'eva

Abstract: The karyotype of the Tsing-Ling (Huanghe) pika, Ochotona huangensis Matschie, 1908 from the forest habitats of the Qinling Mountains (Shaanxi Province, China) was described for the first time. The chromosome set contains 42 chromosomes (NFa=80). The autosomes are 15 meta-submetacentric pairs and 5 subtelocentric pairs. The X chromosome is a medium sized submetacentric; the Y chromosome is a small sized acrocentric. C-banding revealed a localization of heterochromatin in the pericentromeric regions of all autosomes.

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Research Article Mon, 8 Oct 2012 00:00:00 +0300
A comparison of the chromosome G-banding pattern in two Sorex species, S. satunini and S. araneus (Mammalia, Insectivora) https://compcytogen.pensoft.net/article/1763/ Comparative Cytogenetics 6(3): 267-271

DOI: 10.3897/compcytogen.v6i3.3019

Authors: Yuri Borisov, Victor Orlov

Abstract: The G-banded karyotype of S. satunini was compared with the karyotype of Sorex araneus. Extensive homology was revealed. The major chromosomal rearrangements involved in the evolutionary divergence of these species have been identified as centric fusions and centromeric shifts. From the known palaeontological age of S. satunini it is obvious that the vast chromosomal polymorphism of the S. araneus group originated during the middle Pleistocene.

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Research Article Mon, 20 Aug 2012 00:00:00 +0300
A revision of chromosome II (CD) mapping in Chironomus plumosus (Linnaeus, 1758) group (Diptera, Chironomidae) https://compcytogen.pensoft.net/article/1764/ Comparative Cytogenetics 6(3): 249-266

DOI: 10.3897/compcytogen.v6i3.2831

Authors: Veronika Golygina, Iya Kiknadze

Abstract: A revision of the main and alternative banding sequences in chromosome II (CD) has been made for all 14 species of the Chironomus plumosus (Linnaeus, 1758) group. A new version of mapping has been suggested for 10 out of 18 banding sequences of arm C and 12 out of 22 banding sequences of arm D. Mapping of 7 banding sequences has been done for the first time according to the Keyl-Devai system. Phylogenetic relationships of banding sequences of chromosome II have been discussed.

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Research Article Thu, 9 Aug 2012 00:00:00 +0300
Karyotype analysis of four jewel-beetle species (Coleoptera, Buprestidae) detected by standard staining, C-banding, AgNOR-banding and CMA3/DAPI staining https://compcytogen.pensoft.net/article/1751/ Comparative Cytogenetics 6(2): 183-197

DOI: 10.3897/compcytogen.v6i2.2950

Authors: Gayane Karagyan, Dorota Lachowska, Mark Kalashian

Abstract: The male karyotypes of Acmaeodera pilosellae persica Mannerheim, 1837 with 2n=20 (18+neoXY), Sphenoptera scovitzii Faldermann, 1835 (2n=38–46), Dicerca aenea validiuscula Semenov, 1895 – 2n=20 (18+Xyp) and Sphaerobothris aghababiani Volkovitsh et Kalashian, 1998 – 2n=16 (14+Xyp) were studied using conventional staining and different chromosome banding techniques: C-banding, AgNOR-banding, as well as fluorochrome Chromomycin A3 (CMA3) and DAPI. It is shown that C-positive segments are weakly visible in all four species which indicates a small amount of constitutive heterochromatin (CH). There were no signals after DAPI staining and some positive signals were discovered using CMA3 staining demonstrating absence of AT-rich DNA and presence of GC-rich clusters of CH. Nucleolus organizing regions (NORs) were revealed using Ag-NOR technique; argentophilic material mostly coincides with positive signals obtained using CMA3 staining.

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Research Article Fri, 27 Apr 2012 00:00:00 +0300
Presence of the 54-chromosome common vole (Mammalia) on Olkhon Island (Lake Baikal, East Siberia, Russia), and the occurrence of an unusual X-chromosome variant https://compcytogen.pensoft.net/article/1736/ Comparative Cytogenetics 5(5): 433-440

DOI: 10.3897/compcytogen.v5i5.1720

Authors: Svetlana Pavlova, A.V. Tchabovsky

Abstract: We report a new finding of the 54-chromosome sibling species of the common vole in East Siberia - the first description from Olkhon Island (Lake Baikal). The karyotype of a male specimen revealed by routine staining and C-banding demonstrates the unambiguous presence of Microtus rossiaemeridionalis Ognev, 1924 (recently often regarded as as junior synonym of M. levis Miller, 1908). Comparison with conspecific specimens from the European part of the species range (from the left bank of the river Volga) shows that the vole of the island population has a smaller X-chromosome due to a reduced quantity of C-positive heterochromatin. This is just the third example of this type of X-chromosome variant with previous cases on an Arctic island (Svalbard) and the West Siberian lowland (Novosibirsk) and the only one on a lake island. Although M. rossiaemeridionalis is largely monomorphic in its karyotype, our data show that one specific type of X-chromosome variant is remarkably widespread, though rare.

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Research Article Thu, 22 Dec 2011 00:00:00 +0200