GENOME CHARACTERISTICS AND THE SYSTEMATICS OF THE DISCOGLOSSIDAE (AMPHIBIA SALIENTIA)

SUMMARY A comparison has been performed among chromosome sets, genome sizes and DNA fractions characterized by a different repetitivity of the nucleotide sequences in two species of Alytes, one of Discoglossus and one of Bombina (family of Discoglossidae; Amphibia Salientia). Alytes appears as the karyologically less differentiated genus, whereas Bombina distinguishes itself by the sizes of genome and of single-copy fraction, larger than in other discoglossids and outstanding also with respect to the other anurans so far studied; Discoglossus has a karyotype with characteristics transitional between those of the other two genera, but showing a greater complexity in the middle repetitive fraction. These anurans are, therefore, rather heterogeneous and different from one another from the viewpoint of their chromosome morphology and quantitative and qualitative DNA characteristics, so that it is not possible to determine a closer relationship between two of these genera with respect to the third.