Molecular phylogeny of microhylid frogs (Anura: Microhylidae) with emphasis on relationships among New World genera

Abstract

BackgroundOver the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis).ResultsOne mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an unprecedented sampling of 200 microhylid taxa representing 91% of currently recognized subfamilies and 95% of New World genera. Our analyses do not fully resolve relationships among subfamilies supporting previous studies that have suggested a rapid early diversification of this clade. We observed a close relationship between Synapturanus and Otophryne of the subfamily Otophryninae. Within the subfamily Gastrophryninae relationships between genera were well resolved.ConclusionOtophryninae is distantly related to all other New World microhylids that were recovered as a monophyletic group, Gastrophryninae. Within Gastrophryninae, five genera were recovered as non-monophyletic; we propose taxonomic re-arrangements to render all genera monophyletic. This hypothesis of relationships and updated classification for New World microhylids may serve as a guide to better understand the evolutionary history of this group that is apparently subject to convergent morphological evolution and chromosome reduction. Based on a divergence analysis calibrated with hypotheses from previous studies and fossil data, it appears that microhylid genera inhabiting the New World originated during a period of gradual cooling from the late Oligocene to mid Miocene.

Phylogenomics reveals rapid, simultaneous diversification of three major clades of Gondwanan frogs at the Cretaceous–Paleogene boundary

“…Relationships among the subfamilies of Microhylidae (one of the largest anuran families, including 8.8% of all species), which have significant radiations on most continents and the large islands Madagascar and New Guinea, have proven difficult to resolve (4,6,7,(15)(16)(17)(18)(19). In contrast, our Bayesian tree has strong support; all 10 of the deepest nodes have a BPP of 1.0 (Fig.…”

“…The nearly worldwide distribution of Microhylidae presents a longstanding and challenging biogeographic puzzle. Vicariant origin and long-distance oceanic dispersal have been proposed to explain the current distribution of this family (10,15,16,18,23). Which scenario dominates interpretation depends largely on the time and location of origin for the Microhylidae.…”

High resolution images for Phylogeny, taxonomic revision, and character evolution of the genera Chiasmocleis and Syncope (Anura, Microhylidae) in Amazonia, with descriptions of three new species.

“…The only works to include more than one species were those of van der Meijden et al (2007), Pyron and Wiens (2011), and Trueb et al (2011), 2 which included two 2 The phylogenies by Pyron and Wiens (2011) and Trueb et al (2011) derive solely from Genbank data, and the sequences for the two species of Chiasmocleis included by them investigators derive from van der Meijden et al (2007). species of Chiasmocleis (C. hudsoni and C. shudikarensis) in their analysis and found them to form a monophyletic clade, either sister to the remaining Gastrophryninae or sister to all gastrophrynines except Ctenophryne and Nelsonophryne (currently synonyms, de Sá et al, 2012). De Sá et al (2012) included a much larger set of Chiasmocleis and Syncope species, and also included most New World genera of microhylids (missing only Adelastes), thus providing rigorous tests of the monophyly of Chiasmocleis and Syncope and their relationships with other microhylid taxa.…”

“…Prior to de Sá et al (2012), few species of Chiasmocleis (and none of Syncope) were included in any phylogenetic studies using molecular characters (but see Trueb et al, 2011). The only works to include more than one species were those of van der Meijden et al (2007), Pyron and Wiens (2011), and Trueb et al (2011), 2 which included two 2 The phylogenies by Pyron and Wiens (2011) and Trueb et al (2011) derive solely from Genbank data, and the sequences for the two species of Chiasmocleis included by them investigators derive from van der Meijden et al (2007).…”

“…De Sá et al (2012), in a broad phylogenetic analysis of microhylids, included 12 species of Chiasmocleis and three of Syncope (see below), with the two genera recovered as sister taxa. Here, we expand on the dataset of de Sá et al (2012) to aid our evaluation of species diversity of Amazonian Chiasmocleis and Syncope.…”