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We analysed the genetic and bioacoustic variability in Mantidactylus granulatus, a semi arboreal frog species endemic to the northern portion of Madagascar. Advertisement calls had a longer note duration in northeastern as compared to northwestern populations. Specimens from mid altitudes in the Tsaratanana Massif (Northern Central Region) showed distinct call differences. They also had a high sequence differentiation in a fragment of the mitochondrial 16S rRNA gene (pairwise divergence 8.6 %), while all other populations were genetically rather uniform. This Tsaratanana population is described as the new species Mantidactylus zavona; it is also morphologically distinct from the sympatric M. granulatus in that it has a smaller body and a shorter, wider head. The relatively small differences between M. granulatus from different sites in northern Madagascar (pairwise 16S divergences up to 1.4 %), including the isolated Montagne d’Ambre, supports a biogeographic scenario in which the lowland rainforests in this area were connected in Pliocene Pleistocene times. By contrast, the presence of endemic species at higher altitudes of the Tsaratanana Massif may be seen as evidence for a longer isolation of the habitats at these elevational levels.Key words: Amphibia, Mantidactylus granulatus, M. zavona n.sp., advertisement calls, 16S rRNA.

We applied skeletochronological methodology to assess the age and growth in one of the largest living anurans, the mountain chicken, Leptodactylus fallax. We compared bone cross-sections obtained from wild animals, found dead in 2009 after the chytrid outbreak occurred in Montserrat, and captive individuals part of the breeding program at Jersey Zoo. Lines of arrested growth (LAGs) were visible in both groups. Individuals reared in captivity reached an older age than their wild counterparts. Additionally, at the same age, captive males were larger than captive females and wild females were much larger than captive females. A literature screening of age and snout-vent length (SVL) for 46 species (including L. fallax) ascribed to seven families (Bufonidae, Dicroglossidae, Leptodactylidae, Mantellidae, Microhylidae, Ranidae, and Rhacophoridae) showed that the largest species were also the most long-lived. Nevertheless, the position of L. fallax was an outlier (reaching a maximum documented SVL of 280 mm and a maximum longevity of 9 years) in respect to the other species considered. Its body size was larger than expected, indicating a case of gigantism most probably associated with adaptation to an insular environment.

We conducted a rapid amphibian survey of the Atsirakambiaty relict altitude rainforest on Itremo-Ambatofinandrahana Massif, central Madagascar at an altitude of around 1550 m a.s.l. We detected a total of 12 amphibian species, whose taxonomic attributions were confirmed by both morphological and molecular data. Tissue samples were also screened for presence of a lethal chytrid fungus, Batrachochytrium dendrobatidis (Bd), which turned out to be negative. We encourage the herpetological community working in Madagascar to screen regularly amphibian tissue samples for Bd as a tool within the early detection plan recently launched for Madagascar. © NwjZ, Oradea, Romania, 2011.

The morphometry, age structure, and abundance of the panther chameleon Furcifer pardalis (Cuvier 1829) were studied at Nosy Be (NW Madagascar). Males were larger and heavier than Females (SVL, 138.38 +/- 35.94 vs 91.92 +/- 18.48 mm; mass, 61.06 +/- 39.86 vs 22.62 +/- 13.17 g). The age, assessed by skeletochronology, was usually less than one year, with a maximum of 2 years. The density estimate for adult individuals was higher along roads (42.21/ha) than in agricultural habitats far from roads (17.43/ha). Compared to other species of Malagasy chameleons, F pardalis is infrequent in pristine and close forests, while, like other Furcifer species, it. is more closely associated with riverine habitats. The higher concentration Of individuals in forest-like bands along roads is explained by the presence of a suitable vegetation band along roads and the similarity of this habitat to the riverine and ecotonal forests preferred by chameleons of the genus Furcifer. The life history traits, high fecundity and short life span indicate that the current collecting rate does not: affect: the abundance of F pardalis. Measures of chameleon conservation at Nosy Be should consider the preservation of the anthropogenic forest band.

Karyotypes of three microhylid frog species of the Malagasy relict genus Scaphiophryne were studied: Scaphiophryne gottlebei, S. madagascariensis and S. spinosa. The latter two showed a plesiomorphic ranoid karyotype of 2n = 26. In contrast, tetraploidy was demonstrated in S. gottlebei, which constitutes an exceptional state among Malagasy amphibians. A combination of different banding techniques and of rDNA-FISH provided evidence for allopolyploidy in the species and for a completed subsequent functional and structural diploidization. Phylogenetic analysis of mitochondrial 16S rDNA sequences revealed a significant deceleration of nucleotide substitution rates in Scaphiophryne. The tetraploidy of S. gottlebei probably occurred early in their radiation. Ecological and behavioural patterns of Scaphiophryne probably favoured intraspecific gene flow and hybridization events, thereby leading to slow molecular substitution rates and to allopolyploid chromosome speciation in S. gottlebei.

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world’s vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.

The body size and number of eggs in dissected females were analysed in nine species of the Malagasy frog genus Mantella basing upon preserved specimens. These species were distinguished in terms of habitat and grouped as ‘grassland species’ (included M. betsileo, M. expectata, M. viridis), and ‘rainforest species’ (M. baroni, M. crocea, M. cowani, M. laevigata, M. nigricans, M. pulchra). The species with the lowest egg - number was M. cowani with a mean egg number of 37 ± 15, while the species with the highest egg-number was M. viridis with 115 ± 21 eggs. In general, the grassland species are characterised by a higher number of relatively small eggs. Moreover, their fecundity was positively and significantly correlated to female body size. Rainforest species were smaller in size and with a lower number of eggs. We interpreted these differences as possible consequences of habitat adaptations. Among the studied species, the Critically Endangered Mantella cowani is also featured by a low number and large size of eggs. This is likely correlated with the high elevation site of the central highlands where this species occurs.

Andreone, F., Randrianirina, J. E. (2008): An unexpected Rhombophryne record at Tsingy de Bemaraha confirms the presence of cophyline frogs in western Madagascar. Zootaxa 1812 (1): 46-48, DOI: 10.11646/zootaxa.1812.1.2, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1812.1.2

Times Cited: 5; International audience; The black salamander, Salamandra lanzai, exists in isolated and fragmented populations in the Cottian Alps. To examine the degree of intra- and interpopulation divergence, mitochondrial cytochrome b sequences were obtained from samples representing all populations of S. lanzai. No genetic variation was observed either within or among populations. The presence of a single lineage suggests historical explanations closely related to Pleistocene events.