The karyotype of three Brazilian Terrarana frogs (Amphibia, Anura) with evidence of a new Barycholos species

Abstract

A recent substantial rearrangement of the 882 described eleutherodactyline frog species has considerably improved the understanding of their systematics. Nevertheless, many taxonomic aspects of the South American eleutherodactyline species remain unknown and require further investigation using morphological, cytogenetic and molecular approaches. In this work, the karyotypes of the Brazilian species Ischnocnema juipoca (Atibaia and Campos do Jordão, SP), Barycholos cf. ternetzi (Uberlândia, MG, and Porto Nacional, TO), and Pristimantis crepitans (Chapada dos Guimarães and São Vicente, MT) were analyzed using Giemsa staining, Ag-NOR labeling, and C-banding techniques. All individuals had a diploid number of 22 chromosomes, but the Fundamental Numbers were different among species. The herein described low chromosome number of Pristimantis crepitans is unique within this genus, suggesting that cytogenetically this species is not closely related either to its congeneric species or to Ischnocnema. In addition, karyotype differences, mainly in the NOR position, clearly distinguished the two Barycholos populations, besides indicating the existence of a so far undescribed species in this genus. A taxonomic review could clarify the systematic position of P. crepitans and verify the hypothetic new Barycholos species.

Cytogenetic characterization and B chromosome diversity in direct-developing frogs of the genus Oreobates (Brachycephaloidea, Craugastoridae)

“…Oreobates species share a similar morphology of chromosomes, as well as C-banding patterns and the location of NORs. The interstitial heterochromatic band observed in the long arm of pair 6 on specimens of the three species of Oreobates studied here, was not previously reported for Oreobates crepitans by Siqueira et al (2009). However, with the use of similar procedures than these authors for the C-banding protocol, the band was not detectable or was variably marked; suggesting that condensation of chromosomes may play an important role in its detection.…”

“…The genus Oreobates is composed of 23 species (Frost 2015), of which four of them were cytogenetically studied: Oreobates barituensis and Oreobates berdemenos (this work), Oreobates discoidalis (Brum-Zorrilla and Sáez 1968, Schmid 2010, this work), and Oreobates crepitans (Siqueira et al 2009). Oreobates species share a similar morphology of chromosomes, as well as C-banding patterns and the location of NORs.…”

“…In Argentina, the genus is represented by three species, Oreobates berdemenos Pereyra, Cardozo, Baldo & Baldo, 2014, which is phylogenetically related to Oreobates lundbergi and characterized by an incomplete discoidal fold (Pereyra et al 2014); and the cryptic species, Oreobates barituensis Vaira & Ferrari, 2008 and Oreobates discoidalis (Peracca, 1895), recovered as sister species in the most inclusive phylogenetic analyses, both with a complete discoidal fold (Padial et al 2014, Pereyra et al 2014). When compared to other Brachycephaloidea genera, the cytogenetic information available for Oreobates is extremely scarce and only two species were studied to date, Oreobates discoidalis (Brum-Zorilla and Sáez 1968 [as Eleutherodactylus ], Schmid et al 2010), and Oreobates crepitans (Bokermann, 1965) (Siqueira et al 2009, as [ Pristimantis ]). Both taxa share the same chromosome formulae (2n = 22, FN = 44) and similar chromosomal morphology.…”

Priorities for Conservation of the Evolutionary History of Amphibians in the Cerrado

“…Others, like Pristimantis dundeei and Oreobates crepitans are restricted to the region of the cities of Cuiabá and Chapada dos Guimarães at Mato Grosso state. Recent studies indicate that these species are not closely related to others of the same genus, because of their low number of chromosomes and ecological characteristics (Siqueira et al 2009 ), which makes them even more unique.…”

Vocalização de anúncio e ampliação da distribuição de Pristimantis crepitans (Bokermann) (Amphibia, Anura, Strabomantidae)

“…Atualmente, Pristimantis crepitans encontra-se alocada no grupo de P. conspicillatus (PadiaL & de La riva, 2009). Entretanto, divergências citogenéticas com as demais espécies de Pristimantis já analisadas (Siqueira et al, 2008;2009), a singular ocorrência no bioma Cerrado e análises preliminares da ultra-estrutura dos espermatozóides (S. Siqueira, dados inéditos), indicam a possibilidade de uma alocação genérica distinta para P. crepitans (Siqueira et al, 2009).…”