Comparative Cytogenetics in Four <b><i>Leptodactylus</i></b> Species (Amphibia, Anura, Leptodactylidae): Evidence of Inner Chromosomal Diversification in Highly Conserved Karyotypes

With 82 species currently described, the genus <i>Leptodactylus</i> is most diverse and representative one in family Leptodactylidae. Concerning chromosomal organization, this represents an interesting underexplored group since data from molecular cytogenetics are incipient, little known about organization distribution of repetitive DNA elements karyotypes. In sense, study aimed at providing a comparative analysis 4 (<i>L. macrosternum, L. pentadactylus, fuscus,</i> cf<i>. podicipinus</i>), combining conventional (Giemsa staining, C-banding, AgNOR staining) mapping markers (18S rDNA, telomeric microsatellite probes), to investigate mechanisms underlying their karyotype differentiation process. The results showed that all had karyotypes with 2n = 22 FN 44, except for cf. <i>podicipinus</i> which presented 36. 18S rDNA was observed pair 8 analyzed (corresponding <i>L. pentadactylus</i>), coinciding secondary constrictions staining. FISH probes demonstrated species-specific patterns, as well association these sequences constitutive heterochromatin blocks ribosomal clusters, revealing dynamics microsatellites genome species. summary, our demonstrate ongoing process genomic divergence inside almost similar karyotype, driven likely by series pericentric inversions, followed differential accumulation sequences.