title: A frog with highly evolved sex chromosomes.
abstract: Highly differentiated ZZ/ZW sex chromosomes and an exceptionally low genome size were found in the karyotypes of Pyxicephalus adspersus (Anura, Ranidae). The W-chromosome is considerably smaller than the Z-chromosome and consists to a very great proportion of constitutive heterochromatin. The DNA content of this species and the chromosome length have the lowest values determined in the Ranidae to date.
mesh_terms: D000818:Animals; D001001:Anura / Q000235:genetics*; D005075:Biological Evolution; D005260:Female; D008297:Male; D009697:Nucleolus Organizer Region / Q000648:ultrastructure; D012730:Sex Chromosomes / Q000648:ultrastructure*