RESUMO
A new small, semi-arboreal toad of the genus Pelophryne is described from western Sarawak, Malaysian Borneo, on the basis of molecular and morphological evidence. Of the two morphotypes recognized in the genus, the new species belongs to the one in which the tips of the fingers are expanded into truncate discs. Among the species in the morphotype, the new species is most similar to P. murudensis, but differs from it by body size, relative hindlimb length, and dorsal coloration. The new species is currently known only from a limited area on Gunung (= Mt.) Penrissen, and future measures of its habitat conservation are necessary.
Assuntos
Bufonidae/classificação , Distribuição Animal , Animais , Bornéu , Bufonidae/genética , Especificidade da EspécieRESUMO
A fanged frog Limnonectes kuhlii was once thought to be wide-ranging in Southeast Asia, but is now confined to its type locality Java through recent phylogenetic studies, which clarified heterospecific status of non-Javanese populations, and monophyly of Bornean populations. However, large genetic differences among Bornean populations suggest occurrence of cryptic species, which we test using dense geographic sampling. We estimated the phylogenetic relationships among samples of Bornean populations together with their putative relatives from the continental Southeast Asia, using 2517bp sequences of the 12S rRNA, tRNA(val), and 16S rRNA of mitochondrial DNA, and 2367bp sequences of the NCX1, POMC, and RAG1 of nuclear genes. In the mtDNA trees, Bornean L. kuhlii-like frogs formed a monophyletic group split into 18 species lineages including L. hikidai, with the deepest phylogenetic split separating L. cintalubang from the remaining species. Almost all of these lineages co-occur geographically, and two to three lineages were found syntopically in each locality. Co-occurrence of more than one lineage may be maintained by differential morphology and microhabitat selection. These syntopic lineages should be regarded as distinct species. Our results clearly indicate that taxonomic revision is urgent to clarify many evolutionary problems of Bornean L. kuhlii-like frogs.
Assuntos
Anuros/classificação , Variação Genética , Ranidae/classificação , Animais , Anuros/genética , Evolução Biológica , Bornéu , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA Mitocondrial/química , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteínas de Homeodomínio/química , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Filogenia , RNA Ribossômico/química , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Ranidae/genética , Análise de Sequência de DNA , Trocador de Sódio e Cálcio/química , Trocador de Sódio e Cálcio/genética , Trocador de Sódio e Cálcio/metabolismoRESUMO
The jaws of vertebrates display a striking diversity in form and function, but they typically open and close like a trapdoor rather than sliding like a saw. Here, we report unique feeding behaviour in the blunt-headed snail-eating snake, Aplopeltura boa (family Pareidae), where the snake cuts off and circumvents the indigestible part (the operculum) of its prey in the mouth using long sliding excursions of one side of the mandible, while the upper jaws and the mandible on the other side maintain a stable grasp on the prey. This behaviour, which we call 'mandibular sawing', is made possible by extraordinarily independent movements of the jaw elements and is a surprising departure from usual feeding behaviour in vertebrates.