Chiromantis

Abstract: African reed frogs (Hyperolius spp) and tree frogs (Chiromantis spp), an Australian tree frog (Litoria gracilenta) and a South American tree frog (Phyllomedusa azurae) have much lower rates of evaporative water loss from their dorsal skin (0.2 to 2 mg g−1 h−1) than most anuran amphibians, which evaporate water at a rate equivalent to a free water surface. Evaporative water loss rates of Chiromantis, Hyperolius, and Litoria are considerably higher when their ventral skin is exposed. Other anuran amphibians, Hylagratiosa, Agalychnis callidryas, and Afrixalus spp, appear to be moderately waterproof. The mechanism for reduction of evaporative water loss from the skin of the waterproof frogs is unclear, but it appears to involve a lipid barrier. This barrier is disrupted by treatment with a chloroform-methanol mixture. Thin layer chromatographic analysis of lipids extracted from the dorsal and ventral skin of waterproof and nonwaterproof amphibians revealed a considerable variety of neutral and polar lipids. However, few of the lipid components were unique to the dorsal skin of waterproof frogs. We conclude that the presence per se of many of the intradermal lipids (including cholesterol, cholesterol esters, fatty acids, triglycerides, and phospholipids) is not correlated with a waterproofing barrier, although these lipids might contribute to a structural lipid barrier.

Abstract: 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. Resume Evolution des modes de reproduction chez les Rhacophoridae (Amphibia, Anura) Les rainettes de la famille des Rhacophoridae ont differents modes de reproduction: certaines ont un stade tetard alors que d'autres ont un developpement direct, et les adultes de certaines especes fabriquent des nids d’ecume. Philautus est le seul genre caracterise par un developpement direct. La production de nids d’ecume est connue dans les genres Polypedates, Rhacophorus, Chiromantis et Chirixalus. Les recentes etudes moleculaires n'ont pas donne d'hypotheses robustes concernant l'origine de ces modes de reproduction chez les Rhacophoridae. Afin de mieux comprendre l’evolution de ces modes de reproduction, nous avons essaye de clarifier les relations phylogenetiques a l'interieur de ce groupe a l'aide de sequences d'ADN. Notre jeu de donnees consiste en un grand nombre de nouvelles sequences (1676 paires de bases correspondant a trois genes) for cinq extra-groupes de Ranoidea et 48 Rhacophoridae, incluant 16 especes non decrites du Sri Lanka et du sud de l'Inde, et toutes les sequences homologues disponibles sur Genbank. Apres l'inclusion des Philautus d'Inde, nos resultats montrent que la separation de Philautus en clades ne coincide pas avec leur distribution geographique sauf entre la region indienne et les iles de la Sonde. Nos resultats mettent en evidence un clade regroupant les genres Polypedates, Rhacophorus, Chiromantis et Chirixalus. Ce point suggere que la capacitea produire des nids d’ecume n'est apparu qu'une seule fois chez les Rhacophoridae. Une nouvelle taxinomie des Rhacophoridae est proposee, avec une tribu nouvelle, Nyctixalini, reunissant les especes des genres Theloderma et Nyctixalus.