Ctenidae male mitotic and meiotic cells, C-banding and staining with base-specific fluorochromes CMA3 (A, C, E, G, I, K) and DAPI (B, D, F, H, J, L). Arrowhead - X chromosomes. A, B mitotic metaphase of Ctenus ornatus, 28 chromosomes, arrow – interstitial CMA3+ region C, D diakinesis of C. ornatus, Ubatuba population, arrow – bivalent with large CMA3+ block E, F diakinesis of C. medius G, H mitotic metaphase of Phoneutria nigriventer, 2n=28 I, J diakinesis of Viracucha andicola K, L diakinesis of Enoploctenus cyclothorax. Bar = 10 µm.