Chromosome analysis of five Brazilian species of poison frogs (Anura: Dendrobatidae)

Abstract

Dendrobatid frogs have undergone an extensive systematic reorganization based on recent molecular findings. The present work describes karyotypes of the Brazilian species Adelphobates castaneoticus, A. quinquevittatus, Ameerega picta, A. galactonotus and Dendrobates tinctorius which were compared to each other and with previously described related species. All karyotypes consisted of 2n = 18 chromosomes, except for A. picta which had 2n = 24. The karyotypes of the Adelphobates and D. tinctorius species were highly similar to each other and to the other 2n = 18 previously studied species, revealing conserved karyotypic characteristics in both genera. In recent phylogenetic studies, all Adelphobates species were grouped in a clade separated from the Dendrobates species. Thus, we hypothesized that their common karyotypic traits may have a distinct origin by chromosome rearrangements and mutations. In A. picta, with 2n = 24, chromosome features of pairs from 1 to 8 are shared with other previously karyotyped species within this genus. Hence, the A. picta data reinforced that the C-banding pattern and the NOR location are species-specific traits in the genus Ameerega. Moreover, the Ameerega monophyletism proposed by previous phylogenetic studies indicates that the karyotypic differences among species in this genus result from a long divergence time.

Phylogeny of frogs from the genus Physalaemus (Anura, Leptodactylidae) inferred from mitochondrial and nuclear gene sequences

“…In some of the anuran species karyotyped, a single pair of NORs was found in the diploid complement, and this character is apparently fixed in the sampled populations (e.g., Schmid et al, 1978a, b;Lourenço et al, 2000;VeigaMenoncello et al, 2003;Cardozo et al, 2011;Rodrigues et al, 2011). In contrast, multiple NORs as well as interpopulational and/or intrapopulational variations in the numbers or locations of NORs were reported for a number of species of anurans (e.g., Wiley et al, 1989;Foote et al, 1991;Schmid et al, 1995;Kaiser et al, 1996;Bruschi et al, 2014).…”

Chromosomal homology of Uraeotyphlus oxyurus group of species (Amphibia, Gymnophiona, Ichthyophiidae)

“…There are instances that exhibit very little variation in their karyological features. Marked karyological homogeneity seems prevalent in many taxa of cyprinid fishes ( Caputo et al 2003 , Rabova et al 2003 , Mesquita et al 2008 ) and in some salamanders ( Sessions 2008 ) and anuran amphibians ( Kasahara et al 2003 , Aguiar et al 2004 , Rodrigues et al 2011 ) and evidently in cryptodire reptilians ( Olmo 2005 , Castiglia et al 2009 ). Karyological uniformity as demonstrated by some of these studies (including the present report) seems to point towards eliciting closer affiliation in their respective lineages.…”

Ficha de Adelphobates quinquevittatus

“…No Brasil, há registros da espécie nos estados do Acre, Rondônia e sul do Amazonas (Martins & Haddad,1990;Santos et al, 2009;Bernarde et al, 2011;Rodrigues et al, 2011;Neves et al, 2017). É possível que sua distribuição seja mais ampla no país, pois existem ambientes favoráveis à espécie ainda não amostrados.…”