Mantella

About: Mantella is a research topic. Over the lifetime, 92 publications have been published within this topic receiving 2575 citations.

Alkaloids from Australian frogs (Myobatrachidae): pseudophrynamines and pumiliotoxins.

Abstract: Australian frogs of the genus Pseudophryne contain two distinct classes of alkaloids. The pseudophrynamine class (3a-prenyl pyrrolo[2,3-b]indoles) are unique to this genus of frogs of the family Myobatrachidae, while the pumiliotoxin-A class (8-hydroxy-8-methyl-6-alkylidene-1-azabicyclo[4.3.0]nonanes) also occur in dendrobatid frogs of the genera Dendrobates, Epipedobates, and Minyobates, in ranid frogs of the genus Mantella, and in bufonid toads of the genus Melanophryniscus. All seven species of Pseudophryne examined contain both classes of alkaloids. The pseudophrynamines were the predominant class in both species (Pseudophryne guentheri and Pseudophryne occidentalis) from Western Australia, while all of the eastern species (Pseudophryne australis, Pseudophryne bibronii, Pseudophryne coriacea, Pseudophryne corroboree, and Pseudophryne semimarmorata) contained significant amounts of both pseudophrynamines and pumiliotoxins. Pumiliotoxins, in particular pumiliotoxin B, were predominant in two eastern species (P. australis and a southern population of P. corroboree), while pseudophrynamines were dominant in P. bibronii, four of six populations of P. coriacea, one population of P. semimarmorata, and a northern population of P. corroboree. Structures are proposed for several new alkaloids of the pseudophrynamine class.

Systematic revision of the genus Aglyptodactylus Boulenger, 1919 (Amphibia: Ranidae), and analysis of its phylogenetic relationships to other Madagascan ranid genera (Tomopterna, Boophis, Mantidactylus, and Mantella)

Abstract: Recent field studies revealed two new species of the genus Aglyptodactylus (Amphibia: Anura: Ranidae), which was hitherto considered as monotypic and confined to humid eastern Madagascar. Both new species, Aglyptodactylus laticeps sp. n. and Aglyptodactylus securifer sp. n., occur syntopically in the deciduous dry forest of Kirindy in western Madagascar. In comparison to Aglyptodactylus madagascariensis from eastern rainforests, the new species A. laticeps shows a remarkable morphological divergence, which may be partly due to adaptations to burrowing habits in dry environments. Despite of the morphological differentiation, advertisement calls and osteology indicate that all three species of Aglyptodactylus are closely related. A phylogenetic analysis of the Madagascan ranid genera Aglyptodactylus, Mantella, Mantidactylus, Boophis, and Tomopterna (the latter including species from Madagascar, Africa, and Asia) strongly supports a sister group relationship of Aglyptodactylus with the ranine genus Tomopterna. We therefore transfer Aglyptodactylus from the Rhacophorinae to the Raninae and discuss implications of this rearrangement for ranoid systematics. The existence of the endemic genus Aglyptodactylus in Madagascar as well as its close phylogenetic relationships to Tomopterna confirm that the Raninae were already present on the Madagascan plate before its separation from Africa. The Madagascan Tomopterna labrosa shows several important differences both to Asian and to African species of the genus, and is therefore transferred from the subgenus Sphaerotheca (now restricted to Asia) to a new subgenus Laliostoma subgen. n.

Mitochondrial evidence for distinct phylogeographic units in the endangered Malagasy poison frog Mantella bernhardi.

Abstract: Mantella bernhardi is an endemic species of Malagasy poison frog threatened by loss and fragmentation of its natural habitat and collection for the pet trade. It is classified as threatened according to the International Union for Conservation of Nature and Natural Resources (IUCN) categories and included in Appendix II of the Convention on the International Trade of Endangered Species (CITES). A recent survey has increased the known distributional range of the species from one to eight populations across southeastern Madagascar, but little is known about its biology and genetic diversity. Here we estimate inter- and intrapopulation mitochondrial genetic variation of four populations. Populations from the northern and southern parts of the distributional range showed a high degree of divergence (maximum of 11.35% in cytochrome b) and were recovered as reciprocally monophyletic groups. Nine haplotypes were detected in the northern and 12 in the southern populations. The population from Ranomafana National Park showed the lowest number of haplotypes and nucleotide diversity, and shared its most common haplotype with the second northern population from Tolongoina. All the other detected haplotypes were unique to each of the four populations. This suggests the existence of important barriers to gene flow, pre-dating human colonization of Madagascar at about 2000 years ago, in distinct contrast to other Mantella species that show a high degree of haplotype sharing throughout their range. The continued habitat fragmentation within the distribution range of M. bernhardi prevents any connection between its populations. Our data indicate the existence of at least two different management units for conservation in this species, corresponding to the North and South of its distribution range, and highlight the existence of strong regional endemism in southeastern Madagascar.

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

Abstract: 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.