Phylogeny and classification of fejervaryan frogs (Anura: Dicroglossidae)

Systematics and classification of Asian frogs of the genus Fejervarya and related genera (family Dicroglossidae; hereafter referred to as fejervaryan frogs) have been the subject of intensive debates in the past few years. We complement previous phylogenetic studies with analyses of concatenated sequences from 14 nuclear loci and mitochondrial gene fragments, totaling 12,752 nucleotides for 46 species representing all major lineages and relevant outgroups. We find strong support for two major clades within Fejervarya: a South Asian clade and a Southeast Asian clade. Previously, South Asian species have been hypothesized to constitute a separate genus, Zakerana (currently considered a junior synonym of Fejervarya), and also include species previously described as members of the genus Minervarya. Although parsimony and species tree analyses found support for the monophyly of Fejervarya as currently understood, partitioned Bayesian inference and unpartitioned Maximum Likelihood analyses of concatenated sequences recovered Southeast Asian species as a clade sister to the genus Sphaerotheca, albeit with low nodal support. We discuss the advantages and disadvantages of alternative classification schemes in light of previously proposed criteria for naming supraspecific taxa. The current single-genus taxonomy would impart desirable economy of nomenclatural change, and morphological diagnosability. However, other taxon naming criteria such as support for monophyly, temporal framework for diversification, and biogeographic regionalism would support a contrasting two-genus alternative. Because new species of Fejervarya are increasingly being discovered and described, and because a single-genus classification (Fejervarya) will remain controversial, given ambiguous support for its inferred monophyly, we propose recognizing two genera: Southeast Asian Fejervarya, and South Asian Minervarya. This classification results in two genera whose monophyly is strongly supported, respectively, and unlikely to be challenged by future analyses. Accordingly, we transfer all species of the South Asian clade to the genus Minervary