Male meiotic chromosomes of Polididus armatissimus Stål, 1859, n=5AA+XY (2n=10A+XY) A diplotene/diakinesis; heteropycnotic X- and Y-chromosomes form a pseudo-bivalent B, C, D metaphase I/anaphase I transition; X- and Y-chromosomes form a pseudo-bivalent E hybridisation signals of 18S rDNA-FISH (green) and (TTAGG)n-FISH (red) are visible on AAI and on both ends of each chromosome, respectively. Scale bar: 10 μm.