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Astrochelys radiata is one of the threatened tortoise species of Madagascar. We studied their home range size, use of shelters, and diet in Tsimanampetsotsa National Park. The goal was to identify suitable habitats and food chemistry. These data could serve as bases for future evaluations of the suitability of habitats under altered environmental conditions, such as degradation and climate change. The study was performed with the help of radio-tracking in two different types of vegetation: dry deciduous forest on sand and spiny bush on limestone between November 2007 and October 2008. Monthly range sizes were 2.3 ha in the littoral forest and 1.4 ha on the limestone massif when calculated with the kernel method. Based on the minimum convex polygon, the values were 1.0 and 0.5 ha, respectively. Monthly range size did not vary significantly between sexes, but range sizes were larger in the littoral forest than on limestone. A. radiata chose shelters under trees with large trunk diameters ( > 15-cm DBH) and lower heights than trees in representative samples in the habitats. Plant items eaten and not eaten by this species were analyzed for primary and secondary plant chemicals. A. radiata consumed a wide variety of plants. Its diet was composed of leaves (91%), flowers (5%), and fruits (4%) from 109 plant species. During the dry season, high energy content was the most important factor for food selection by A. radiata. [ABSTRACT FROM AUTHOR]

The article reports on the recovery of three helminths, including Oochoristica chavenoni, Abbreviata madagascariensis, and Hexametra angusticaecoides, in the small intestines of Malagsy lizards collected from three sites in Madagascar. The lizards represent three species including Calumma brevicorne, Furcifer verrucosus, and Paroedura picta. It appears that lizard helminths in the area have been isolated geographically and evolved separately from those on the African continent.

The article presents research which assessed the association between the Phesulma standingi and the Adansonia in Madagascar. The researchers examined the role played by the Phesulma standingi in offering secure refuge as well as climbing surfaces for the large day geckos. They also found that the association between baobab and the Phesulma standingi is only related with large mature trees that belong to the species of Adansonia za, Adansonia grandidieri and the Adansonia rubrostipa. The authors suspected that Phesulma standingi is widely distributed in Madagascar despite the claims that it is only known to occupy the river drainages Fiherenana, Mangoky and Onilahy.

The Geckolepis fish-scale geckos, which exhibit extreme skin and scale autotomy, and are endemic to Madagascar and the Comoros, have long been considered problematic concerning species recognition, with the last review of the group made by Angel (1942). Here we report the results of our morphological study, which examined 178 specimens representing most of the intact museum specimens that are currently available. We find a total of three valid species within the genus Geckolepis: G. typica Grandidier, 1867; G. maculata Peters, 1880; and G. polylepis Boettger, 1893. We consider three previously described taxa: G. petiti Angel, 1942; G. typica anomala Mocquard, 1909; and G. typica modesta Methuen and Hewitt, 1913, as junior synonyms of G. typica; and G. humbloti Vaillant, 1887, as a junior synonym of G. maculata. We designate MNHN 1994.1748 as the lectotype of Geckolepis typica. For each recognized species we provide a diagnosis and new description, summarize individual variation, and describe geographical distribution. We also present an identification key for the group and discuss systematic and biogeographic issues and the unusual scale fragility of Geckolepis. [ABSTRACT FROM AUTHOR]

The radiated tortoise (Astrochelys radiata), endemic to the spiny forest of southern Madagascar, had virtually never been studied in the wild until the late 1990s. Recent research projects and surveys have contributed to defining the extent of the decline of the species, and it now appears that A. radiata faces serious extinction risks unless current trends are halted. As part of an ongoing conservation genetics project concerning the species, we investigated genetic diversity and differentiation of the isolated tortoise population from Parc National d'Andohahela (PNA), considered as one of the last remaining sanctuaries of the species in the southeast, where Antanosy people consume tortoise meat. Genetic diversity at PNA was similar to other populations, but differentiation was the greatest of all sites sampled, emphasizing the conservation value of this population. However, our most important finding was that the majority of captured tortoises at PNA were relatively small males, indicating that recruitment may be very low. We found physical evidence that Antanosy poachers are removing the largest individuals from the population, despite their official protection within the park. We discuss conservation issues related to A. radiata, including the role of protected areas in Madagascar, the importance of understanding the taboo toward tortoises in Antandroy and Mahafaly communities, and the pertinence of the current Convention on International Trade in Endangered Species listing of the species. [ABSTRACT FROM AUTHOR]

One of the predicted biological responses to climate warming is the upslope displacement of species distributions. In the tropics, because montane assemblages frequently include local endemics that are distributed close to summits, these species may be especially vulnerable to experiencing complete habitat loss from warming. However, there is currently a dearth of information available for tropical regions. Here, we present a preliminary appraisal of this extinction threat using the herpetological assemblage of the Tsaratanana Massif in northern Madagascar (the island's highest massif), which is rich with montane endemism. We present meteorological evidence (individual and combined regional weather station data and reanalysis forecast data) for recent warming in Madagascar, and show that this trend is consistent with recent climate model simulations. Using standard moist adiabatic lapse rates, these observed meteorological warming trends in northern Madagascar predict upslope species displacement of 17–74 m per decade between 1993 and 2003. Over this same period, we also report preliminary data supporting a trend for upslope distribution movements, based on two surveys we completed at Tsaratanana. For 30 species, representing five families of reptiles and amphibians, we found overall mean shifts in elevational midpoint of 19–51 m upslope (mean lower elevation limit 29–114 m; mean upper elevation limit −8 to 53 m). We also found upslope trends in mean and median elevational observations in seven and six of nine species analysed. Phenological differences between these surveys do not appear to be substantial, but these upslope shifts are consistent with the predictions based on meteorological warming. An elevational range displacement analysis projects complete habitat loss for three species below the 2 °C ‘dangerous’ warming threshold. One of these species is not contracting its distribution, but the other two were not resampled in 2003. A preliminary review of the other massifs in Madagascar indicates potential similar vulnerability to habitat loss and upslope extinction. Consequently, we urgently recommend additional elevational surveys for these and other tropical montane assemblages, which should also include, when possible, the monitoring of local meteorological conditions and habitat change. [ABSTRACT FROM AUTHOR]

A fundamental expectation of vicariance biogeography is for contemporary cladogenesis to produce spatial congruence between speciating sympatric clades. The Uroplatus leaf-tailed geckos represent one of most spectacular reptile radiations endemic to the continental island of Madagascar, and thus serve as an excellent group for examining patterns of continental speciation within this large and comparatively isolated tropical system. Here we present the first phylogeny that includes complete taxonomic sampling for the group, and is based on morphology and molecular (mitochondrial and nuclear DNA) data. This study includes all described species, and we also include data for eight new species. We find novel outgroup relationships for Uroplatus and find strongest support for Paroedura as its sister taxon. Uroplatus is estimated to have initially diverged during the mid-Tertiary in Madagascar, and includes two major speciose radiations exhibiting extensive spatial overlap and estimated contemporary periods of speciation. All sister species are either allopatric or parapatric. However, we found no evidence for biogeographic congruence between these sympatric clades, and dispersal events are prevalent in the dispersal–vicariance biogeographic analyses, which we estimate to date to the Miocene. One sister-species pair exhibits isolated distributions that we interpret as biogeographic relicts, and two sister-species pairs have parapatric distributions separated by elevation. Integrating ecological niche models with our phylogenetic results finds both conserved and divergent niches between sister species. We also found substantial intra-specific genetic variation, and for the three most widespread species, poor intra-specific predictive performance for ecological niche models across the latitudinal span of Madagascar. These latter results indicate the potential for intra-specific niche specialization along environmental gradients, and more generally, this study suggests a complex speciation history for this group in Madagascar, which appears to include multiple speciation processes. [ABSTRACT FROM AUTHOR]