Systematic revision of Microhyla (Microhylidae) frogs of South Asia: a molecular, morphological, and acoustic assessment

This study presents a systematic revision of South Asian members of the taxonomically challenging genus Microhyla Tschudi, 1838. Species relationships and diagnostic characters are determined by integrating molecular, morphological, and acoustic approaches, through which we also recognize six groups of closely related species. In addition, a new species from the southern Western Ghats of India is formally described as Microhyla darreli sp. nov. Species accounts of all the 16 recognized members from South Asia include current taxonomic status, metric and meristic characters, divergence in mitochondrial DNA, phylogenetic relationships, acoustic characters, revised geographical distributions, and natural history notes. Molecular and morphological relationships of three poorly known members — M. chakrapanii, M. karunaratnei, and M. zeylanica — are clarified for the first time since their original descriptions. The presence of M. berdmorei and another potential new species close to M. heymonsi in India is genetically confirmed, and several misidentifications are corrected. For comparative purposes, molecular, morphological, and acoustic relationships are also discussed for eight closely related East and Southeast Asian species. Consequently, insights from this study will facilitate a much-needed comprehensive revision of the Pan-Asian frog genus Microhyla