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We report results of a morphological and ecological study on the funnel-mouthed tadpoles of litter frogs in the subgenus Chonomantis, genus Mantidactylus, from Madagascar. The larvae of these riparian frogs are characterized by umbelliform oral discs and absence of well developed keratodonts. Based on specimens identified by DNA barcoding we provide general morphological descriptions for the larvae of all eight nominal species plus two candidate species of Chonomantis, and describe the buccal anatomy of seven species. We detected only minor morphometric differences amongst species in mainly the relative size of the oral disc. In addition we found one candidate species (here named Mantidactylus sp. 59) to be characterized by rudimentary keratodont rows, Mantidactylus brevipalmatus by enlarged lungs, and Mantidactylus aerumnalis by a distinct colour pattern. Ecological data gathered in 30 streams in the Ranomafana area indicated important abundance differences amongst species. Mantidactylus melanopleura and Mantidactylus opiparis, which are the two most widespread species over Madagascar, were also locally most abundant in Ranomafana but interestingly showed no diagnostic morphological differences and fully overlapped in morphometric variables. Microhabitat choice of Chonomantis in Ranomafana was characterized by a clear preference for slow-moving stretches of streams with a substrate of submerged dead leaves. In general Chonomantis tadpoles were thus remarkably similar in their morphology and ecology. Considering the high degree of sympatric occurrence, with up to five species of the subgenus co-occurring along the same stream, this indicates a rather low influence of larval competition in creating selective pressures for specialization in these frogs. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162, 149–183.

The larval morphology of Madagascan frogs of the family Microhylidae, subfamilies Dyscophinae and Scaphiophryninae, is described based on material from the genera Dyscophus ( D. insularis ), Paradoxophyla ( P. palmata ) and five species of the enigmatic genus Scaphiophryne : S. brevis , S. calcarata , S. madagascariensis , S. menabensis and S. spinosa . The latter are known to have larvae that are intermediate between the filter-feeding larval type typical for most microhylids and the generalized tadpole of most ranoid and hyloid frogs. However, the two detailed descriptions available to date, referring to Scaphiophryne calcarata and S. gottlebei , pointed to important differences in size and oral morphology within Scaphiophryne . Our data confirm that all studied Scaphiophryne have horny beaks but lack keratodonts and are to be referred to the psammonektonic ecomorphological guild. Scaphiophryne brevis and S. calcarata have rather small tadpoles (up to 22 mm total length) whereas S. madagascariensis , S. menabensis and S. spinosa , as well as S. gottlebei , have larger tadpoles (up to 48 mm total length) with a striking distance between the skin and the internal organs, giving the head and body a balloon-like appearance. These two morphological tadpole groups agree with previously published molecular phylogenetic data and support the classification of these species in the two subgenera Pseudohemisus and Scaphiophryne . The larva of the genus Paradoxophyla , the sister group of Scaphiophryne , has a typical microhylid filter-feeding morphology and shares many synapomorphies with other microhylids. Since a convergent evolution of these features is unlikely, the ancestors of Scaphiophryne appear to have re-acquired their beak and other characters that at first view are plesiomorphic. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 555‐576. ADDITIONAL KEYWORDS: amphibia ‐ DNA barcoding ‐ Dyscophus insularis ‐ Madagascar ‐ Microhylidae ‐ Paradoxophyla palmata ‐ phylogeny ‐ tadpole morphology.

We describe the larval stages of three species of the Asian-African tiger frogs Hoplobatrachus chinensis, H. occipitalis and H. tigerinus. The tadpoles of all three species are very similar, with peculiar oral features: (1) double rows of needle-like labial teeth, (2) strong emarginations on the large jaw sheaths and (3) keratinized spurs on the buccal floor. Characters 1 and 2 (and perhaps 3) are probably related to the carnivorous habits of these tadpoles. A molecular phylogeny based on 2430 base pairs of two nuclear and four mitochondrial genes corroborated monophyly of Asian and African Hoplobatrachus, and identified Euphlyctis as their sister group. Tadpoles of the latter genus lack buccal spurs and double labial tooth rows but share large jaw sheaths, the upper with a medial projection. Therefore, the common ancestor of Euphlyctis and Hoplobatrachus probably was also characterized by this state, and may have been facultatively carnivorous. Further carnivorous specializations in Hoplobatrachus could explain why tiger frogs have been so successful in populating arid environments where ponds are at high risk of desiccation. Larval morphology may prove to be the key innovation which enabled them to disperse, in the Late Cenozoic, into their current very wide distribution area in Asia and Africa. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 81, 171–181.