Chromosome Banding in Amphibia. XXXI. The Neotropical Anuran Families Centrolenidae and Allophrynidae

Abstract

The mitotic chromosomes of 11 species from the anuran families Centrolenidae and Allophrynidae were analyzed by means of conventional staining, banding techniques, and in situ hybridization. The amount, location, and fluorochrome affinities of constitutive heterochromatin, the number and positions of nucleolus organizer regions, and the patterns of telomeric DNA sequences were determined for most of the species. The karyotypes were found to be highly conserved with a low diploid chromosome number of 2n = 20 and morphologically similar chromosomes. The sister group relationship between the Centrolenidae and Allophrynidae (unranked taxon Allocentroleniae) is clearly corroborated by the cytogenetic data. The existence of heteromorphic XY♂/XX♀ sex chromosomes in an initial stage of morphological differentiation was confirmed in Vitreorana antisthenesi. The genome sizes of 4 centrolenid species were determined using flow cytometry. For completeness and for comparative purposes, all previously published cytogenetic data on centrolenids are included.

Cytogenetic analysis of the genus Thoropa Cope, 1865 (Anura-Cycloramphidae) with evolutionary inferences based on repetitive sequences

“…Overall, the results point to a conserved karyotype in the group, since the species and different populations presented the same chromosome number (2n = 26), fundamental number (FN = 52) and chromosome morphology, including the presence of a secondary constriction in the long arm of pair 6 ( Figure 1). In addition, heterochromatic bands were identified only in telomeres and centromeres ( Figure 2), an expected pattern for anurans (Schmid et al, 2014).…”

Unraveling the Sex Chromosome Heteromorphism of the Paradoxical Frog Pseudis tocantins

“…Sex chromosomes are present in organisms with GSD, resulting in male heterogamety (as observed in mammals) or female heterogamety (common in birds and snakes). In amphibians, both male and female heterogamety are present (reviewed in [ 3 ] and [ 4 ]), but heteromorphic sex chromosomes may be recognized in only a few species [ 4 , 5 ]. Among anurans, approximately 40 species display heteromorphic sex chromosomes, which include cases of multiple sex chromosome systems (e.g., [ 6 ]) and 00/0W system [ 7 ], besides the usual XX/XY and ZZ/ZW systems (reviewed in [ 4 ]).…”

Cytogenetic and genetic data support Crossodactylus aeneus Müller, 1924 as a new junior synonym of C. gaudichaudii Duméril and Bibron, 1841 (Amphibia, Anura)

“…Cytogenetic data have provided important insights into interspecific comparisons in many groups, helping in evolutionary analyses. In cytogenetic studies of anurans, the NOR has been used as a valuable chromosome marker for the differentiation of species (Schmid et al, 2014) and even populations (Silva et al, 1999;Quinderé et al, 2009;Nascimento et al, 2019), although in several cases, the location of the NOR varies little among closely-related species (Busin et al, 2008;Cardozo et al, 2011). When we compared the karyotypes of C. gaudichaudii and C. aeneus based on diploid number, FN, NOR location, mapping of PcP190 satellite DNA and mapping of (CA) 15 and (GATA) 8 microsatellite clusters, no differences were found.…”