Molecular phylogeny, morphology and bioacoustics reveal five additional species of arboreal microhylid frogs of the genus Anodonthyla from Madagascar

We provide a partial revision of the microhylid frogs of the genus Anodonthyla, endemic to Madagascar, based on comprehensive molecular, bioacoustic and morphological data sets that include newly collected specimens from multiple localities. The molecular trees provide strong evidence for the polyphyly of several nominal species as they were previously defined, especially of Anodonthyla boulengeri and A. nigrigularis. As a consequence, we here resurrect the nomen Mantella pollicaris Boettger as Anodonthyla pollicaris from the synonymy of A. boulengeri, and we describe four new species, all with strong genetic divergences to other nominal species: Anodonthyla emilei from Ranomafana National Park, a comparatively medium-sized species characterized by a multi-note advertisement call with high note repetition rate; A. theoi from Manombo Special Reserve, a small species characterized by low note repetition rate, long note duration and high spectral call frequency; A. vallani, a medium-sized species from Ambohitantely Special Reserve, characterized by low note repetition rate, long note duration and low spectral call frequency; and A. jeanbai, a small species from Andohahela National Park, characterized by a long and narrow head, presence of short dorsolateral folds, a very short first finger, and a yellowish ventral colour. A further candidate species comprises populations previously assigned to A. boulengeri from the Ranomafana region, which we do not describe because the corresponding data set is too fragmentary, and we refer to it as A. sp. aff. boulengeri 'Ranomafana'. The molecular phylogeny indicates recurrent shifts between high and low note repetition rates in calls, based mainly on three strongly supported sister groups: A. moramora with low repetition rate and A. nigrigularis with moderately low repetition rate; A. theoi with low repetition rate and A. pollicaris with high repetition rate; and A. vallani with low repetition rate and A. sp. aff. boulengeri 'Ranomafana' with high repetition rate. The two species with the northernmost ranges, A. hutchisoni and A. boulengeri, are phylogenetically nested within clades of species occurring further south, confirming that the center of origin of the genus Anodonthyla was most likely in the South East of Madagascar.