Rhacophorid treefrogs have different reproductive modes: some go through a tadpole stage and some have direct development, and the adults of some species produce foam nests. Philautus is the only genus characterized by direct development. The production of foam nests has been reported in the genera Polypedates, Rhacophorus, Chiromantis and Chirixalus. Recent molecular studies did not provide a robust hypothesis concerning the origin of these reproductive modes in the Rhacophoridae. In order to better understand the evolution of these reproductive modes, we tried to clarify relationships within this group, using DNA sequencing. Our data set consists in a large number of new sequences (1676 base pairs corresponding to threee genes) for five outgroup ranoids and 48 Rhacophoridae, including 16 undescribed species from Sri Lanka and southern India, and all homologous data available in Genbank. After the inclusion of Philautus from India, our data show that the separation of Philautus into clades does not coincide with their geographic distribution. Our data point to the existence of a clade, including the genera Rhacophorus, Polypedates, Chiromantis and Chirixalus, which confirms the results of Wilkinson et al. (2002) and suggests that the ability to produce foam nests has emerged only once in the Rhacophoridae, as already stated by these authors.

The morphology of tadpoles has long received too little attention in taxonomic and phylogenetic contexts, beyond the use of Orton’s general tadpole types, despite the potential of larval characters for resolving problems in systematics. A possible explanation for this neglect is the ontogenetic variation of external morphology. In order to understand the value of larval characters in taxonomy and systematics, it is necessary to determine the developmental stage at which characters reach their definitive size, form and colour before meaningful comparisons can be made within and between species. Here I use the tadpole of Rana (Sylvirana) nigrovittata as a model organism to assess ontogenetic character variation. Morphometric measurements were taken, and external oral and internal buccal characters were assessed separately for each developmental stage from 26 to 38. Coefficients of variation were calculated for each morphometric character at each stage of development to test the character’s efficiency in reflecting the morphology of the tadpole. Most morphometric characters taken from the body described the shape of the animal well and varied little among individuals, whereas those taken from the tail were less reliable and those of the oral disk were quite variable due to contraction during fixation. A developmental 'climax' for most characters was reached by specimens between stages 32-40, indicating that they are best suited for morphological intra- and interspecific comparisons.

Amphibian populations are dramatically declining, while their inventory is far from being achieved. Tadpoles are usually overlooked from biodiversity survey, whereas their consideration will optimize species counts and knowledge of their ecological and developmental requirements is essential in conservation planning. Two mitochondrial markers, 16S (397 new sequences obtained) and COI (343 new sequences obtained), are used to test DNA barcoding on a set of larval and adult Asian amphibians represented by 83 recognized species from 65 sites. The advantages and drawbacks of each marker are assessed, COI barcoding being advocated for global DNA barcoding, whereas 16S suits for taxonomically or geographically restricted DNA barcoding. About half of the collected tadpoles were badly identified or incompletely named in the field. All tadpole sequences (except one case of probable introgressive hybridization) were correctly assigned to their respective species. Finally six clusters of tadpole sequences without conspecific adults were revealed, stressing the importance of collecting and taking into account tadpoles in biodiversity survey and conservation planning.

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.

Based on specimens identified by DNA barcoding, we describe the tadpoles of 11 species of treefrogs (Boophis) in the Malagasy family Mantellidae. All tadpoles belong to species of the stream-breeding clade within Boophis. Based on these and other published descriptions of Boophis tadpoles which develop in running water bodies, we tentatively distinguish three ecomorphological guilds for these larvae. Guild A, in which we describe the larvae of B. boehmei, B. reticulatus, B. pyrrhus, B. tasymena, and B. viridis which have few lotic adaptations, their oral disc width being 31-43% of body width, with a single row of 48-81 marginal papillae, and the first upper keratodont row having 58-144 keratodonts. Guild B, in which we describe the tadpoles of B. albilabris, B. madagascariensis, B. luteus, and of an undescribed species here named B. sp. aff. elenae, is intermediate, with an enlarged oral disc, an increasing number of keratodont rows and a lower height of the caudal fin. In these tadpoles, oral disc width is 43-63% of body width, they have one or two rows of 69-164 marginal papillae, and the first upper keratodont row has 164-238 keratodonts. Guild C contains tadpoles with a very large oral disc, living on submerged rocks and stones in stream sections of strong current. In this guild we describe the tadpoles of B. marojezensis and B. sibilans. Their oral disc width is 63-89% of body width, there are multiple rows of many marginal papillae, and the first upper keratodont row has many small keratodonts which are difficult to count, but consistently amount to over 200. In B. marojezensis, the dorsal gap in the marginal papillae rows, apparent in all other species, is closed. These larval morphologies show a rather good fit with recently published molecular phylogenetic data: species groups that were confirmed to be monophyletic in most cases have similar larval morphologies, and, in contrast, where species of the same group have disparate larval morphologies the monophyly of the group is questionable (e.g. the B. majori group). Nevertheless, some cases of convergent evolution are apparent, such as the highly specialized Guild C morphology, which may have evolved separately in the B. albipunctatus group, B. mandraka group, and in some species of the B. majori group.

Frogs in the subgenus Lalos of the genus Leptolalax (Megophryidae) are highly diversified in continental Asia and consist of about 17 nominal species. These frogs are small, inconspicuous, and of high superficial morphological similarity.        We here formulate a hypothesis of phylogenetic relationships and assess the amount of genetic variation among genealogical lineages on the basis of 536bp of mitochondrial 16S rDNA sequences. Combining molecular data with a study of morpho-logy, morphometric divergence and geographical proximity, we tested hypotheses of species identity. We (1) used character-based and morphometric analyses to assign the onymophoronts (type specimens) of species in Lalos available to us to respectively one of the main clades, in order to propose the best potential correct taxonomic and nomenclatural allocation for the individuals included in the molecular study, and (2) tried to also assign the historical museum specimens to these molecular taxonomic units and to reclassify them whenever necessary.        We also used the molecular data to match tadpoles with adults and provide tadpole descriptions for species the larvae of which were previously unknown. Specimens, that could neither be allocated to a molecularly characterised species (on the basis of their DNA “barcode”) nor to a morphologically defined species named on the basis of a type specimen, are described here as new species. Based on this integrative set of data and analyses we describe two new species, Leptolalax eos n. sp. and Leptolalax nyx n. sp., we resurrect Leptolalax minimus, and reassess the distribution of the species studied. We propose changes in the Red List status of L. pelodytoides and L. ventripunctatus and suggest a conservation status for the new species described herein.

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.

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.