Fanomezana M. Ratsoavina

Hiding deep in the trees: discovery of divergent mitochondrial lineages in Malagasy chameleons of the Calumma nasutum group

We conducted a comprehensive molecular phylogenetic study for a group of chameleons from Madagascar (Chamaeleonidae: Calumma nasutum group, comprising seven nominal species) to examine the genetic and species diversity in this widespread genus. Based on DNA sequences of the mitochondrial gene (ND2) from 215 specimens, we reconstructed the phylogeny using a Bayesian approach. Our results show deep divergences among several unnamed mitochondrial lineages that are difficult to identify morphologically. We evaluated lineage diversification using a number of statistical phylogenetic methods (general mixed Yule-coalescent model; SpeciesIdentifier; net p-distances) to objectively delimit lineages that we here consider as operational taxonomic units (OTUs), and for which the taxonomic status remains largely unknown. In addition, we compared molecular and morphological differentiation in detail for one particularly diverse clade (the C. boettgeri complex) from northern Madagascar. To assess the species boundaries within this group we used an integrative taxonomic approach, combining evidence from two independent molecular markers (ND2 and CMOS), together with genital and other external morphological characters, and conclude that some of the newly discovered OTUs are separate species (confirmed candidate species, CCS), while others should best be considered as deep conspecific lineages (DCLs). Our analysis supports a total of 33 OTUs, of which seven correspond to described species, suggesting that the taxonomy of the C. nasutum group is in need of revision.

Extinction Risks and the Conservation of Madagascar's Reptiles

Background An understanding of the conservation status of Madagascars endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the islands mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the islands biodiversity.

Calumma vohibola, a new chameleon species (Squamata: Chamaeleonidae) from the littoral forests of eastern Madagascar

Abstract We describe Calumma vohibola sp. nov., a morphologically distinct chameleon species of the Calumma nasutum species group from littoral forest fragments of the north-central east coast of Madagascar. Males and females of this species differ from all other species of the Calumma nasutum group by an almost absent rostral appendage, by a characteristic stress colouration in the female consisting of a dark reddish ground colouration with many irregular light blue spots, and by significant sequence divergence in the mitochondrial ND2 gene (10.5–19.4% pairwise distance) and no haplotype sharing in the nuclear C-mos gene compared with other members of the C. nasutum group. A molecular survey of C. nasutum populations occurring near the type locality of the new species reveals an extraordinarily high genetic diversity within this morphologically conservative chameleon group. We suspect that C. vohibola might be restricted to a rather small and fragmented distribution range within the last littoral forest fragments along the coast. Owing to the unsolved taxonomic situation of the C. nasutum group, no reliable distribution data of any member of this group are available at present, and hence we cannot ascertain whether the extent of occurrence of C. vohibola is indeed as restricted as suspected. Intensive surveys and field studies are necessary to clarify the distribution limits of this new species and to assess its conservation status reliably.

Northern origin and diversification in the central lowlands? – Complex phylogeography and taxonomy of widespread day geckos (Phelsuma) from Madagascar

Day geckos of the Phelsuma lineata group are widespread in Madagascar and have been historically split into numerous species and subspecies based almost exclusively on differences in coloration and body size. We apply phylogenetic and phylogeographic methods to examine the biogeography and taxonomy of these lizards, including explicit tests of various biogeographic predictions and based on a molecular data set covering much of the distribution ranges of all species and subspecies of P. lineata, P. dorsivittata, P. comorensis, P. hoeschi, P. kely, and P. pusilla in Madagascar (and the Comoros archipelago for P. comorensis). Sequences of the mitochondrial 16S rRNA and the nuclear RAG-1 gene fragment were determined from 376 samples, and a multigene mtDNA phylogeny of the species group was constructed for the main phylogroups identified in the 16S haplotype network. We used the 16S sequences to estimate the geographic location of the ancestor of each major mtDNA clade and to infer their demographic history using a variety of statistical tools. Our phylogeny separates the taxa analyzed into two well-supported major subclades mainly occurring in the north respectively east of the island. Mismatch distribution of samples together with rejection of neutrality, the results of Bayesian Skyline Plots analysis, and a star-like network suggests a recent demographic expansion for the P. l. lineata lineage into the eastern lowlands, while the highland (P. l. elanthana) and northern clades (P. dorsivittata and P. l. punctulata) show signatures of rather stable populations. A major genetic discontinuity observed coincided with a northern lowland stretch that separates mid-altitude rainforests in the north from those in the center and south. Our analysis points to numerous unsolved taxonomic problems in this group of geckos, especially in the small-sized taxa (P. hoeschi, P. kely, P. pusilla), and provides a basis for a future comprehensive taxonomic revision, which will require integrative analysis of molecular, morphological and chromatic data as well as careful examination of type specimens.

A likely microendemic new species of terrestrial iguana, genus Chalarodon, from Madagascar.

A new species of the hitherto monotypic genus Chalarodon is described from southern Madagascar and a lectotype (ZMB 4360) is designated for C. madagascariensis Peters, 1854. The new species of terrestrial iguana, Chalarodon steinkampi sp. nov., is defined by several morphological characters and by concordant differentiation in mitochondrial and nuclear DNA with >5% uncorrected pairwise genetic distance in the 16S rRNA gene. It can be most clearly recognized by the presence of smooth (vs. keeled) gular and ventral scales, a spotted pattern extending from flanks onto belly, and an unpigmented throat. The new species is known from only a small area between the villages of Amboasary Sud and Esomony, located west of the Andohahela Massif, while C. madagascariensis appears to be widespread over much of southern and western Madagascar. We highlight the need for further exploration of this unprotected region which might host several other microendemic species.

A new leaf-tailed gecko of the Uroplatus ebenaui group (Squamata: Gekkonidae) from Madagascar's central eastern rainforests.

We describe a new leaf-tailed gecko species of the Uroplatus ebenaui group from the eastern central rainforests of Madagascar, which had previously been considered as a confirmed candidate species. Our description of Uroplatus fiera sp. nov. relies on integrating evidence from molecular and morphological characters and is based on newly collected material from two localities. A phylogenetic analysis based on multiple mitochondrial DNA fragments places the new species as sister to a lineage of uncertain status (Uroplatus ebenaui [Ca8]), and the clade consisting of these two lineages is sister to a further undescribed candidate species (U. ebenaui [Ca1]). This entire clade is sister to U. phantasticus plus another candidate species. The new species differs from these close relatives, and all other congenerics, by strong differences in DNA sequences of mitochondrial genes (>8.5% uncorrected p-distance in 16S rDNA to all nominal species of the genus) and lacks shared alleles with any of the nominal species in the nuclear CMOS gene. From its closest relatives the new species further differs in its much smaller tail size (relative to U. phantasticus), and a narrower tail, fewer supralabials, and more toe lamellae (relative to U. ebenaui [Ca1]). Morphologically the new species is most similar to U. ebenaui but differs in its larger body size and unpigmented oral mucosa. Given its distribution in central eastern Madagascar, with records from near Fierenana and Ambatovy, its range overlaps with that of U. phantasticus. Based on examination of the U. phantasticus holotype, we confirm that this latter has a blackish pigmented oral mucosa as do those specimens typically attributed to this nomen, thereby confirming its distinctness from U. fiera sp. nov., in which the mucosa is unpigmented.

Two new species of leaf-tailed geckos ( Uroplatus ) from the Tsaratanana mountain massif in northern Madagascar

The Tsaratanana Massif is the highest mountain massif of Madagascar and is characterized by a high species-level endemism of its biota. Here we describe two new small-sized species of leaf-tailed geckos of the Uroplatus ebenaui group from this region. Named in a preliminary way as confirmed candidate species Uroplatus ebenaui [Ca1] and [Ca2] in previous studies, we here provide detailed data on their molecular and morphological differentiation and describe them as Uroplatus fotsivava sp. nov. and Uroplatus kelirambo sp. nov. Their closest relatives are U. fiera and U. finiavana, respectively, as revealed by a phylogeny based on DNA sequences of four mitochondrial genes. However, integration of various lines of evidence confirms that the new species are independent evolutionary lineages, differing from other Uroplatus by high mitochondrial divergences, lack of haplotype sharing in the nuclear CMOS gene, and shape and relative size of the tail. While U. fotsivava is known from multiple sites at elevations between 1100-1538 m above sea level, U. kelirambo was found only at high elevations between 2000-2200 m a.s.l.; it therefore is the only known forest-dwelling nocturnal gecko reaching such high elevations in Madagascar, and might be narrowly endemic to montane forests of the Tsaratanana Massif.