title: Karyological confirmation of conspicuous ZW sex chromosomes in two species of Pacific anguilloid fishes (Anguilliformes: Teleostomi).
abstract: Leukocyte and kidney cell cultures were used to examine the sex chromosomes of Japanese freshwater eels (Anguilla japonica) and conger eels (Astroconger myriaster). The conspicuous presence of ZW sex chromosomes, due to a drastic reduction in size of the W, was confirmed in both species, where the Z was the largest metacentric and the W was the smallest metacentric in a diploid karyotype of 38 chromosomes in both species. These species are the first examples of the ZW type of heteromorphism in eels.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004524:Eels / Q000235:genetics*; D005260:Female; D007668:Kidney / Q000648:ultrastructure; D007962:Leukocytes / Q000648:ultrastructure; D008297:Male; D012730:Sex Chromosomes; D013045:Species Specificity