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Purpose: Despite Madagascar's high amphibian diversity of more than 400 species, only a few polystome species are known from the island. The dissection of frogs from museum collections, together with amphibian and parasite surveys conducted in Madagascar led to the discovery of an undescribed polystome infecting Aglyptodactylus madagascariensis. The purpose of this study is to formally describe this species. Methods: Polystomes recovered from A. madagascariensis were stained (Acetocarmine) and mounted (Canada balsam) to facilitate morphometrics and taxonomic drawings. Some specimens were fixed in absolute alcohol, a Bayesian tree inferred from the analysis of concatenated 18S, 28S and COI gene sequences was constructed and pairwise distances were calculated. Parasites collected from archived hosts in museums were used for histology and scanning electron microscopy (SEM). Results: Polystomes recovered from A. madagascariensis display characteristics of the genus Metapolystoma and morphologically differed from all other known metapolystomes. The Bayesian phylogeny shows that Metapolystoma n. sp. ex. A. madagascariensis and M. falcatum are sister species with high Bayesian posterior probability. Histological and SEM investigations contributed to morphological descriptions. Conclusions: Morphological examination supported by phylogenetic analysis and genetic divergences revealed distinct differences from all known metapolystome species, supporting the description of a new species. Differences between the life cycles of Metapolystoma and Polystoma provided additional evidence for the validity of that genus as taxon. Whereas Polystoma may display ovoviviparity on rare occasions after incomplete egg expulsion towards the end of the breeding season, Metapolystoma displays true ovoviviparity. We emphasize the need for parasite surveys in Madagascar and recommended for museum material to be examined for polystomes to provide supplementary material and localities for further field investigation. [ABSTRACT FROM AUTHOR]

A range-wide assessment of genetic variation in one mitochondrial (16S rRNA) and one nuclear-encoded (Rag-1) gene fragment of the widespread Madagascar frog Blommersia blommersae revealed the presence of up to 12 deep genetic lineages. Many of these differed by genetic distances >3% in the 16S gene. In the Ranomafana area in the southern central east of Madagascar, two mitochondrial lineages differing by 1.2–1.8% in 16S occurred in close syntopy across multiple sites. A phylogeny of representative samples based on multiple mitochondrial genes supported three main mitochondrial clades within B. blommersae, with lineages from the (i) north, (ii) north and northern central east, and (iii) southern central east, respectively. In addition, one lineage from Sainte Luce in the south-east was sister to all other species of Blommersia, and thus clearly not belonging to B. blommersae, to which it has been tentatively assigned previously. Except for the Sainte Luce population, most of the mitochondrial lineages did not show a concordant and consistent differentiation in Rag-1 and no obvious morphological differences were detected among the lineages. We therefore refrain from taxonomic conclusions for them at this time, although indications exist that the populations from the northern central east and southern central east may show certain differences in relative note duration of advertisement calls, which require further study. However, the Sainte Luce individuals were highly divergent in 16S (>10%) and Rag-1, phylogenetically isolated, and characterised by differences in colour pattern. This lineage represents the most evolutionarily divergent species of Blommersia known to date and is herein formally named and described as Blommersia dupreezi sp. nov. [ABSTRACT FROM AUTHOR]

How environmental factors shape patterns of biotic diversity in tropical ecosystems is an active field of research, but studies examining the possibility of ecological speciation in terrestrial tropical ecosystems are scarce. We use the isolated rainforest herpetofauna on the Montagne d'Ambre (Amber Mountain) massif in northern Madagascar as a model to explore elevational divergence at the level of populations and communities. Based on intensive sampling and DNA barcoding of amphibians and reptiles along a transect ranging from ca. 470–1470 m above sea level (a.s.l.), we assessed a main peak in species richness at an elevation of ca. 1000 m a.s.l. with 41 species. The proportion of local endemics was highest (about 1/3) at elevations >1100 m a.s.l. Two species of chameleons (Brookesia tuberculata, Calumma linotum) and two species of frogs (Mantidactylus bellyi, M. ambony) studied in depth by newly developed microsatellite markers showed genetic divergence up the slope of the mountain, some quite strong, others very weak, but in each case with genetic breaks between 1100 and 1270 m a.s.l. Genetic clusters were found in transect sections significantly differing in bioclimate and herpetological community composition. A decrease in body size was detected in several species with increasing elevation. The studied rainforest amphibians and reptiles show concordant population genetic differentiation across elevation along with morphological and niche differentiation. Whether this parapatric or microallopatric differentiation will suffice for the completion of speciation is, however, unclear, and available phylogeographic evidence rather suggests that a complex interplay between ecological and allopatric divergence processes is involved in generating the extraordinary species diversity of Madagascar's biota. Our study reveals concordant patterns of diversification among main elevational bands, but suggests that these adaptational processes are only part of the complex of processes leading to species formation, among which geographical isolation is probably also important. [ABSTRACT FROM AUTHOR]

Microbial diversity positively influences community resilience of the host microbiome. However, extinction risk factors such as habitat specialization, narrow environmental tolerances, and exposure to anthropogenic disturbance may homogenize host-associated microbial communities critical for stress responses including disease defense. In a dataset containing 43 threatened and 90 non-threatened amphibian species across two biodiversity hotspots (Brazil's Atlantic Forest and Madagascar), we found that threatened host species carried lower skin bacterial diversity, after accounting for key environmental and host factors. The consistency of our findings across continents suggests the broad scale at which low bacteriome diversity may compromise pathogen defenses in species already burdened with the threat of extinction. [ABSTRACT FROM AUTHOR]

The study of diamond frogs (genus Rhombophryne, endemic to Madagascar) has been historically hampered by the paucity of available specimens, because of their low detectability in the field. Over the last 10 years, 13 new taxa have been described, and 20 named species are currently recognized. Nevertheless, undescribed diversity within the genus is probably large, calling for a revision of the taxonomic identification of published records and an update of the known distribution of each lineage. Here we generate DNA sequences of the mitochondrial 16S rRNA gene of all specimens available to us, revise the genetic data from public databases, and report all deeply divergent mitochondrial lineages of Rhombophryne identifiable from these data. We also generate a multi-locus dataset (including five mitochondrial and eight nuclear markers; 9844 bp) to infer a species-level phylogenetic hypothesis for the diversification of this genus and revise the distribution of each lineage. We recognize a total of 10 candidate species, two of which are identified here for the first time. The genus Rhombophryne is here proposed to be divided into six main species groups, and phylogenetic relationships among some of them are not fully resolved. These frogs are primarily distributed in northern Madagascar, and most species are known from only few localities. A previous record of this genus from the Tsingy de Bemaraha (western Madagascar) is interpreted as probably due to a mislabelling and should not be considered further unless confirmed by new data. By generating this phylogenetic hypothesis and providing an updated distribution of each lineage, our findings will facilitate future species descriptions, pave the way for evolutionary studies, and provide valuable information for the urgent conservation of diamond frogs. [ABSTRACT FROM AUTHOR]

In order to improve the molecular resources available for conservation management of Madagascar's threatened ichthyofauna, we elaborated a curated database of 2860 mitochondrial sequences of the mitochondrial COI, 16S and ND2 genes of Malagasy fishes, of which 1141 sequences of freshwater fishes were newly sequenced for this data set. The data set is mostly composed of COI (2015 sequences) while 16S and ND2 sequences from partly the same samples were used to match the COI sequences to reliably identified reference sequences of these genes. We observed COI uncorrected pairwise genetic distances of 5.2‒31.0% (mean 20.6%) among species belonging to different genera, and 0.0‒22.4% (mean 6.4%) for species belonging to the same genus. Deeply divergent mitochondrial lineages of uncertain attribution were found among Malagasy freshwater eleotrids and gobiids, confirming these groups are in need of taxonomic revision. DNA barcodes assigned to introduced cichlids (tilapias) included Coptodon rendallii, C. zillii, Oreochromis aureus (apparently a new country record), O. cf. mossambicus, O. niloticus, and one undetermined species of Oreochromis, with sequences of up to three species found per location. In aplocheiloid killifishes of the genus Pachypanchax, most species from northern Madagascar had only low mitochondrial divergences, three of these species (P. omalonotus, P. patriciae, and P. varatraza) were not reciprocally monophyletic, and one genetically deviant lineage was discovered in a northern locality, suggesting a need for partial taxonomic revision of this genus. While the lack of voucher specimens for most of the samples sequenced herein precludes final conclusions, our first step towards a DNA barcoding reference library of Madagascar's fishes already demonstrates the value of such a data set for improved taxonomic inventory and conservation management. We strongly suggest further exploration of Madagascar's aquatic environments, which should include detailed photographic documentation and tissue sampling of large numbers of specimens, and collection of preserved voucher specimens as well as of living fish for the buildup of ex situ assurance populations of threatened species complying with the One Plan Approach proposed by the IUCN SSC Conservation Breeding Specialist Group (CBSG). [ABSTRACT FROM AUTHOR]

Horizontal transfer (HT) of genes between multicellular animals, once thought to be extremely rare, is being more commonly detected, but its global geographic trend and transfer mechanism have not been investigated. We discovered a unique HT pattern of Bovine-B (BovB) LINE retrotransposons in vertebrates, with a bizarre transfer direction from predators (snakes) to their prey (frogs). At least 54 instances of BovB HT were detected, which we estimate to have occurred across time between 85 and 1.3 Ma. Using comprehensive transcontinental sampling, our study demonstrates that BovB HT is highly prevalent in one geographical region, Madagascar, suggesting important regional differences in the occurrence of HTs. We discovered parasite vectors that may plausibly transmit BovB and found that the proportion of BovB-positive parasites is also high in Madagascar where BovB thus might be physically transported by parasites to diverse vertebrates, potentially including humans. Remarkably, in two frog lineages, BovB HT occurred after migration from a non-HT area (Africa) to the HT hotspot (Madagascar). These results provide a novel perspective on how the prevalence of parasites influences the occurrence of HT in a region, similar to pathogens and their vectors in some endemic diseases. [ABSTRACT FROM AUTHOR]

In the processes that give rise to new species, changes first occur at the population level. But with the continuous nature of the divergence process, change in biological properties delimiting the shift from "individuals of divergent populations" towards "individuals of distinct species", as well as abiotic factors driving the change, remain largely ambivalent. Here we study diversification processes at the population level in a semi-aquatic frog, Mantidactylus (Brygoomantis) bellyi, across the diverse vegetation types of Montagne d'Ambre National Park (MANP), Madagascar. Genetic diversity was assessed with seven newly developed microsatellite markers as well as mitochondrial DNA sequences and concordance with patterns of ecological, morphological, and bioacoustic divergence evaluated. We found M. bellyi lacking mitochondrial differentiation within MANP, while microsatellite datasets partitioned them into three highly differentiated, geographically separated subpopulations (with indications for up to five subpopulations). The molecular grouping–primarily clustering individuals by geographic proximity–was coincident with differences in mean depth and width of waters, suggesting a possible role of fluvial characteristics in genetic exchange in this stream-breeding species. Genetic clustering not consistent with differences in call properties, except for dominant call frequencies under the two-subpopulations model. Morphological divergence was mostly consistent with the genetic clustering; subpopulations strongly differed by their snout-vent length, with individuals from high-elevation subpopulations smaller than those from populations below 1000 m above sea level. These results exemplify how mountains and environmental conditions might primarily shape genetic and morphological divergence in frog populations, without strongly affecting their calls. [ABSTRACT FROM AUTHOR]

The stump-toed frogs of the Madagascar-endemic genus Stumpffia are mostly diminutive in size, but there is one group of comparatively large frogs within the genus, which we herein refer to as the Stumpffia hara species group. Each of the four known members of this species group is endemic to a single location of deciduous dry forest with exposed karstic limestone rock. Here, we report on the discovery of members of this species group on Montagne d'Ambre, a rainforest-covered extinct volcano in the North of Madagascar that has a rich Stumpffia fauna but has been thought to lack members of the S. hara species group until now. We found two members of the species group, one at the peak, and one in transitional and dry deciduous forest on the west and northern slopes of the mountain. The high-elevation species is new to science, and we here describe it as Stumpffia bishopi sp. nov. It occupies a highly distinct position in the phylogeny of these frogs, characterized by = 9.8% uncorrected pairwise distance from all other nominal Stumpffia in a fragment of the mitochondrial 16S rRNA gene. It is also the smallest of the members of the S. hara species group. Our genetic results show that the low-elevation species is Stumpffia megsoni, constituting a range expansion of that species and considerably expanding our understanding of its morphology and ecology. We report its advertisement call for the first time. Our results highlight the importance of continued surveys of even well-sampled localities, with special attention on the high elevation sites of northern massifs and collection of voucher specimens, and how much there still remains to understand about even the largest of Madagascar's small frogs. [ABSTRACT FROM AUTHOR]

Biological invasions are on the rise, with each invader carrying a plethora of associated microbes. These microbes play important, yet poorly understood, ecological roles that can include assisting the hosts in colonization and adaptation processes or as possible pathogens. Understanding how these communities differ in an invasion scenario may help to understand the host's resilience and adaptability. The Asian common toad, Duttaphrynus melanostictus is an invasive amphibian, which has recently established in Madagascar and is expected to pose numerous threats to the native ecosystems. We characterized the skin and gut bacterial communities of D. melanostictus in Toamasina (Eastern Madagascar), and compared them to those of a co-occurring native frog species, Ptychadena mascareniensis, at three sites where the toad arrived in different years. Microbial composition did not vary among sites, showing that D. melanostictus keeps a stable community across its expansion but significant differences were observed between these two amphibians. Moreover, D. melanostictus had richer and more diverse communities and also harboured a high percentage of total unique taxa (skin: 80%; gut: 52%). These differences may reflect the combination of multiple host-associated factors including microhabitat selection, skin features and dietary preferences. [ABSTRACT FROM AUTHOR]

The subgenus Mantidactylus is a group of frogs endemic to Madagascar, including the largest anuran species on the island. Although these frogs are common and widely distributed, their taxonomy remains unclear. Two species are currently recognised, M. grandidieri and M. guttulatus, with another available name, Rana pigra, considered to be a synonym of M. grandidieri. However, molecular studies have suggested the presence of several cryptic species within the group. Additionally, due to the lack of prominent morphological features, allocating the available names to evolutionary lineages has proven challenging. In the present study, we take a first step towards solving these problems by using fragments of the 16S mitochondrial gene and RAG1 nuclear gene from all over the range of the subgenus to describe its genetic diversity. We also use a newly designed target enrichment laboratory protocol to sequence three mitochondrial fragments from five name-holding museum specimens (as old as 120 years) in order to determine to which lineages the existing names should be applied. The study of the 16S mitochondrial gene revealed 7 geographically separated lineages, distinct enough to be considered candidate species. Out of the five museum specimens analysed, four successfully yielded DNA sequences and could be attributed to one of the aforementioned lineages. Therefore, the name Mantidactylus grandidieri should be applied to the populations from North-Eastern Madagascar, while M. guttulatus refers to populations from inland localities along the Eastern coast of the island. On the other hand, the holotype of Rana pigra did not yield enough genetic material to allow definitive identification. While our data were not sufficient to assess the status of the four lineages distributed along the Eastern coast, the populations from North-Western Madagascar were highly distinct on both the mitochondrial and nuclear markers. We thus describe them as a new species, M. radaka sp. nov. [ABSTRACT FROM AUTHOR]

Using the land‐bound vertebrates on the marine islands as model organisms, two metrics are presented that permit quantitative and succinct synopses of the 'evolutionary maturity' of the hosted faunal assemblages. In turn, these reflect the geo‐physical settings and geological developments of the substrates. The assemblage lineage‐taxonomy spectrum (ALTS) is based on the constituent lineages' taxonomic distinctiveness and diversity. Individual lineages within assemblages can in most cases be assigned to one of six categories, LT1‒LT6: LT1 is a non‐endemic taxon, whereas LT6 comprises multiple endemic genera from a family that arose elsewhere. If required, the scheme can be expanded: LT9 is an endemic order. The data can then be combined to provide an assemblage spectrum, for example, 00:08:38:30:08:15[13]. Here, the first six values denote the number of lineages assigned to each category expressed as percentages of the overall total, with the sum of the processed lineages listed as the seventh (in brackets and bold). The ALTS metric highlights efficiently the key features of a marine island's biological assemblage. Notably, the contrast between spectra for suites on geologically and geo‐physically varied island types can be striking, for instance the squamate suite on the young, proximate orogenic margin island of Taiwan is coded 78:16:05:00:00:00[37] whereas the one on the distantly located, Late Eocene composite terrane island of New Caledonia is 00:11:00:11:33:44[9]. To overcome the subjectivity that is inherent in assigning supraspecific ranks, an alternative assemblage lineage‐age spectrum (ALAS) is also introduced that makes use of the binary logarithm values of the colonization times of the island lineages (0–2, 2–4, ... , 32–64, >64 Ma). It is represented using a seven‐plus‐two‐number code, for instance Madagascar's squamates are 00:06:00:00:19:62:12[19(16)]; most colonizations took place in the Palaeogene (66–23 Ma); there are 19 lineages, but only 16 are presently age‐dated. In addition to marine‐island biogeography studies, the ALTS–ALAS spectrum approach is potentially useful for encapsulating biotas in other sorts of insular setting (e.g. lakes, mountain tops), and for evaluating palaeogeographical models. Furthermore, it may help emphasize the conservation value of an island's faunal assemblage. [ABSTRACT FROM AUTHOR]

The bacterial communities colonizing amphibian skin have been intensively studied due to their interactions with pathogenic chytrid fungi that are causing drastic amphibian population declines. Bacteria of the family Alcaligenaceae, and more specifically of the genus Pigmentiphaga, have been found to be associated specifically to arboreal frogs. Here we analyze their occurrence in a previously assembled global skin microbiome dataset from 205 amphibian species. Pigmentiphaga made up about 5% of the total number of reads in this global dataset. They were mostly found in unrelated arboreal frogs from Madagascar (Mantellidae and Hyperoliidae), but also occurred at low abundances on Neotropical frogs. Based on their 16S sequences, most of the sequences belong to a clade within Pigmentiphaga not assignable to any type strains of the five described species of the genus. One isolate from Madagascar clustered with Pigmentiphaga aceris (>99% sequence similarity on 16S rRNA gene level). Here, we report the full genome sequence of this bacterium which, based on 16S sequences of >97% similarity, has previously been found on human skin, floral nectar, tree sap, stream sediment and soil. Its genome consists of a single circular chromosome with 6,165,255 bp, 5,300 predicted coding sequences, 57 tRNA genes, and three rRNA operons. In comparison with other known Pigmentiphaga genomes it encodes a higher number of genes associated with environmental information processing and cellular processes. Furthermore, it has a biosynthetic gene cluster for a nonribosomal peptide syntethase, and bacteriocin biosynthetic genes can be found, but clusters for β-lactones present in other comparative Pigmentiphaga genomes are lacking. [ABSTRACT FROM AUTHOR]

Taxonomy is the cornerstone of extinction risk assessments. Currently, the IUCN Red List treats species complexes either under a single overarching species name—resulting in an unhelpfully broad circumscription and underestimated threat assessment that does not apply to any one species lineage—or omits them altogether—resulting in the omission of species that should be assessed. We argue that taxonomic uncertainty alone, as in species complexes, should be grounds for assessment as Data Deficient (DD). Yet, use of the DD category is currently discouraged, resulting in assessments based on poor data quality and dismissal of the importance of taxonomic confidence in conservation. This policy may be leading to volatile and unwarranted assessments of hundreds of species across the world, and needs to be revised. To illustrate this point, we here present a partial taxonomic revision of torrent frogs from eastern Madagascar in the Mantidactylus subgenus Hylobatrachus. Two named species, Mantidactylus (Hylobatrachus) lugubris and M. (H.) cowanii, and several undescribed candidate species are recognised, but the application of the available names has been somewhat ambiguous. In a recent re-assessment of its conservation status, M. (H.) lugubris was assessed including all complex members except M. (H.) cowanii within its distribution, giving it a status of Least Concern and distribution over most of eastern Madagascar. After describing two of the unnamed lineages as Mantidactylus (Hylobatrachus) atsimo sp. nov. (from southeastern Madagascar) and Mantidactylus (Hylobatrachus) petakorona sp. nov. (from the Marojejy Massif in northeastern Madagascar), we show that Mantidactylus (Hylobatrachus) lugubris is restricted to the central east of Madagascar, highlighting the inaccuracy of its current Red List assessment. We propose to re-assess its status under a more restrictive definition that omits well-defined candidate species, thus representing the actual species to which its assessment refers, to the best of current knowledge. We recommend that for species complexes in general, (1) nominal lineages that can be confidently restricted should be assessed under the strict definition, (2) non-nominal species-level lineages and ambiguous names should be prioritised for taxonomic research, and (3) ambiguous names should be assessed as DD to highlight the deficiency in data on their taxonomic status, which is an impediment to their conservation. This would reduce ambiguity and underestimation of threats involved in assessing species complexes, and place the appropriate emphasis on the importance of taxonomy in anchoring conservation. [ABSTRACT FROM AUTHOR]

We describe the new gecko species Paroedura neglecta sp. n. from the Tsingy de Bemaraha National Park in western Madagascar, belonging to the P. bastardi/tanjaka clade. The species in this clade are characterized by three light dorsal crossbands on the dorsum of juveniles and subadults whereas all other Paroedura species have four such bands. The new species differs from all species in the P. bastardi complex in having the nostril in contact with the rostral scale. It is most similar to the sympatric P. tanjaka, from which it differs by the presence of prominent dorsal tubercles arranged in regular longitudinal rows (versus rather irregular rows of dorsal tubercles), smaller size, details of the dorsal colour pattern and strong genetic divergence. [ABSTRACT FROM AUTHOR]

Miniaturised frogs form a fascinating but poorly understood amphibian ecomorph and have been exceptionally prone to taxonomic underestimation. The subfamily Cophylinae (family Microhylidae), endemic to Madagascar, has a particularly large diversity of miniaturised species which have historically been attributed to the single genus Stumpffia largely based on their small size. Recent phylogenetic work has revealed that several independent lineages of cophyline microhylids evolved towards highly miniaturised body sizes, achieving adult snout–vent lengths under 16 mm. Here, we describe five new species belonging to three clades that independently miniaturised and that are all genetically highly divergent from their relatives: (i) a new genus (Mini gen. nov.) with three new species from southern Madagascar, (ii) one species of Rhombophryne, and (iii) one species of Anodonthyla. Mini mum sp. nov. from Manombo in eastern Madagascar is one of the smallest frogs in the world, reaching an adult body size of 9.7 mm in males and 11.3 mm in females. Mini scule sp. nov. from Sainte Luce in southeastern Madagascar is slightly larger and has maxillary teeth. Mini ature sp. nov. from Andohahela in southeast Madagascar is larger than its congeners but is similar in build. Rhombophryne proportionalis sp. nov. from Tsaratanana in northern Madagascar is unique among Madagascar’s miniaturised frogs in being a proportional dwarf, exhibiting far less advanced signs of paedomorphism than other species of similar size. Anodonthyla eximia sp. nov. from Ranomafana in eastern Madagascar is distinctly smaller than any of its congeners and is secondarily terrestrial, providing evidence that miniaturisation and terrestriality may be evolutionarily linked. The evolution of body size in Madagascar’s microhylids has been more dynamic than previously understood, and future studies will hopefully shed light on the interplay between ecology and evolution of these remarkably diverse frogs. [ABSTRACT FROM AUTHOR]

Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800–1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of suitable habitat occupied by a species, is less expressed in amphibians than in reptiles, possibly reflecting their lower dispersal capacity. Taxonomic composition of communities assessed by field surveys is largely explained by bioclimatic regions, with communities from the dry and especially subarid biomes distinctly differing from humid and subhumid biomes. [ABSTRACT FROM AUTHOR]

Madagascar hosts a high diversity of amphibians estimated at over 500 species, nearly all of them endemic. Surprisingly few data are available on the activity cycles of this fauna, despite its importance for ecological, evolutionary and conservation research. Here we report the results of a year-round survey of amphibians along a transect bordering the Analamazaotra forest near Andasibe in central eastern Madagascar. During 120 transect walks evenly spaced through the year, a total of 2530 individuals of 40 species of anurans was observed. Abundance was higher during the warm/rainy season (December to April) and peaked in February. Of the five climatic predictors measured, only mean temperature and relative humidity showed high importance values, and multi-model averages indicate that these two variables have a strong effect on amphibian abundance along the transect. Species richness showed no evident peak during the study period and was best explained by a model including average temperature and rainfall. Canonical correspondence analysis indicates thatBoophis sibilans, B. tephraeomystax, B. boehmeiandPlethodontohyla notostictawere more frequently encountered along the transect on cold and humid days whilePlethodontohyla mihanika, Gephyromantis boulengeriandSpinomantis aglaveiwere distinctly more abundant on cold and dry days, andParadoxophyla palmataon warm and dry days. The results of our study flag a number of species as suitable candidates for future monitoring initiatives and suggest that a simple combination of visual and acoustic surveys can estimate amphibian activity with high sample sizes in Madagascar’s rainforests. [ABSTRACT FROM PUBLISHER]

Scincine lizards in Madagascar form an endemic clade of about 60 species exhibiting a variety of ecomorphological adaptations. Several subclades have adapted to burrowing and convergently regressed their limbs and eyes, resulting in a variety of partial and completely limbless morphologies among extant taxa. However, patterns of limb regression in these taxa have not been studied in detail. Here we fill this gap in knowledge by providing a phylogenetic analysis of DNA sequences of three mitochondrial and four nuclear gene fragments in an extended sampling of Malagasy skinks, and microtomographic analyses of osteology of various burrowing taxa adapted to sand substrate. Based on our data we propose to (i) consider Sirenoscincus Sakata & Hikida, 2003, as junior synonym of Voeltzkowia Boettger, 1893; (ii) resurrect the genus name Grandidierina Mocquard, 1894, for four species previously included in Voeltzkowia; and (iii) consider Androngo Brygoo, 1982, as junior synonym of Pygomeles Grandidier, 1867. By supporting the clade consisting of the limbless Voeltzkowia mira and the forelimb-only taxa V. mobydick and V. yamagishii, our data indicate that full regression of limbs and eyes occurred in parallel twice in the genus Voeltzkowia (as hitherto defined) that we consider as a sand-swimming ecomorph: in the Voeltzkowia clade sensu stricto the regression first affected the hindlimbs and subsequently the forelimbs, whereas the Grandidierina clade first regressed the forelimbs and subsequently the hindlimbs following the pattern prevalent in squamates. Timetree reconstructions for the Malagasy Scincidae contain a substantial amount of uncertainty due to the absence of suitable primary fossil calibrations. However, our preliminary reconstructions suggest rapid limb regression in Malagasy scincids with an estimated maximal duration of 6 MYr for a complete regression in Paracontias, and 4 and 8 MYr respectively for complete regression of forelimbs in Grandidierina and hindlimbs in Voeltzkowia. [ABSTRACT FROM AUTHOR]

We provide new morphological and genetic data on a poorly studied genus of geckos from Madagascar ( Paragehyra) previously thought to be distributed only in the south-east and south-west of the island and discuss the biogeography and evolution of this genus. Two species ( Paragehyra petiti and Paragehyra gabriellae) were formerly included in this genus, whose phylogenetic and biogeographical relationships remain unresolved. This morphological and molecular study enables the recognition of two new rock-dwelling species that are here formally described. Paragehyra felicitae sp. nov. has only been observed in the private Anja reserve and nearby areas (close to Ambalavao) on the southern central high plateau of Madagascar, whereas Paragehyra austini sp. nov. is known from only one locality on the western slopes of the Andohahela massif, around 60 km northwest of Tolagnaro. The four species differ from one another by a combination of several morphological characters, genetic divergence >5.2 % in a mitochondrial 16S ribosomal RNA (rRNA) gene fragment and nucleotide differences in analysed nuclear genes, as highlighted in the resulting phylogenetic reconstruction and haplotype network analysis. A further, hitherto unstudied Paragehyra population is known from the Tsingy de Bemaraha in central-western Madagascar. Preliminary information of its morphological differentiation are here provided and suggest that this undescribed species is closely related to P. petiti and P. felicitae sp. nov. [ABSTRACT FROM AUTHOR]

The pseudoxyrhophiine snake genus Liopholidophis Mocquard, 1904 (family Lamprophiidae) is endemic to Madagascar and according to its present definition comprises six medium-sized, terrestrial and diurnal snake species, most of which are characterised by an unusual and extreme sexual dimorphism in tail length. We performed molecular phylogenetic analyses using nucleotide sequences of three mitochondrial genes (16S rRNA, cytochrome b and cytochrome oxidase I) and one nuclear gene (c-mos) for all described and two additional species newly described herein. The two new species are very small sized (total length: 234-312.5 mm), have comparatively short tails and a reduced number of dorsal scale rows (15 at midbody), the lowest value among all non-scolecophidian snakes of Madagascar. Both species are secretive or rare, and they have a reddish belly in life that fades in preservative. In terms of colouration and morphology, they are most similar to each other and furthermore to Liopholidophis rhadinaea. Together with this species and L. dimorphus, they form a well-supported clade. Liopholidophis baderi sp. nov. from central eastern Madagascar is characterised by 149-158 ventrals and 71-77 subcaudals, whereas the similar L. oligolepis sp. nov. from the northeast has even fewer ventrals (137) and subcaudals (54). The phylogenetic tree suggests that the tail length dimorphism in the genus Liopholidophis has evolved in a complex pattern including at least one reversal. The phylogenetic position of the two new dwarf species indicates that both the absence of extreme sexual dimorphism in tail length and their body size reduction are derived and probably correlated features. Also the close phylogenetic relationships between the long-tailed L. sexlineatus and the similar but relatively short-tailed L. varius demonstrate that dimorphism in tail length can be strongly mitigated in short evolutionary time periods. [ABSTRACT FROM AUTHOR]

Madagascar is a biodiversity hotspot with a unique fauna and flora largely endemic at the species level and highly threatened by habitat destruction. The processes underlying population-level differentiation in Madagascar's biota are poorly understood and have been proposed to be related to Pleistocene climatic cycles, yet the levels of genetic divergence observed are often suggestive of ancient events. We combined molecular markers of different variability to assess the phylogeography of Madagascar's emblematic tomato frogs ( Dyscophus guineti and D. antongilii) and interpret the observed pattern as resulting from ancient and recent processes. Our results suggest that the initial divergence between these taxa is probably old as reflected by protein-coding nuclear genes and by a strong mitochondrial differentiation of the southernmost population. Dramatic changes in their demography appear to have been triggered by the end of the last glacial period and possibly by the short return of glacial conditions known as the 8K event. This dramatic change resulted in an approximately 50-fold reduction of the effective population size in various populations of both species. We hypothesize these species' current mitochondrial DNA diversity distribution reflects a swamping of the mitochondrial genetic diversity of D. guineti by that of D. antongilii previous to the populations' bottlenecks during the Holocene, and probably as a consequence of D. antongilii demographic expansion approximately 1 million years ago. Our data support the continued recognition of D. antongilii and D. guineti as separate species and flag D. guineti as the more vulnerable species to past and probably also future environmental changes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar’s colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island’s biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island’s paleogeographical evolution to determine how particular events influenced the arrival of the island’s extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar’s tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island’s isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar’s extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar’s unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more recently arriving clades. Thus, the composition of Madagascar’s endemic vertebrate assemblage itself provides evidence of the island's paleogeographic history. [ABSTRACT FROM AUTHOR]

Many tropical rainforests harbour species-rich assemblages of frogs and, consequently, of tadpoles. These larvae are often morphologically highly diverse, especially in their oral structures. Whether this might represent an important axis of ecological partitioning in frog assemblages remains an untested hypothesis. In general, it is poorly known how diverse tadpole assemblages are organised. Using information from Madagascar's remarkably species-rich stream tadpole assemblages, we analysed the distribution and co-occurrence of 44 species. We also assessed the importance of phylogenetic history and eco-morphological adaptation for habitat selection at two functional and two spatial levels. We show that both rare and common species exist in most morphological clusters and phylogenetic groups of tadpoles. Habitat characteristics of the streams and surrounding forest influence species composition. Whereas there is a general trend in preferring wide and deep streams without a steep slope for most species, some of the morphological clusters separate along specific habitat variables. Stream choice is influenced both by phylogenetic history and morphological adaptation. Within streams, tadpoles partition microhabitat mainly according to their morphological cluster but without phylogenetic signal. Species dissimilarities of habitat selection on both spatial scales are not correlated. We found no evidence for competition in the tadpole assemblages studied. [ABSTRACT FROM AUTHOR]

We describe a new frog species of the genus Guibemantis in the subgenus Pandanusicola from southeastern Madagascar and provide a redescription of a morphologically similar species, C. pulcher, based on its type series and on newly collected material. The new species, Guibemantis tasifotsy, differs from most Pandanusicola by probably not breeding in leaf axils of Pandanus plants but instead was collected calling from the vegetation above large, open lowland swamps. The green dorsal color of the new species is reminiscent of Guibemantis pulcher but can be distinguished from this Pant/anus breeding species by the presence of prominent white blotches along the flanks and by the structure of femoral glands in males. It shares these character states with C. liber from which the new species differs in details of coloration and advertisement call. Newly determined DNA sequences of the cytochrome b gene confirm that C. tasifotsy is genetically highly divergent from all other species of Guibemantis, [ABSTRACT FROM AUTHOR]

Based on concordant differences in male advertisement call, tadpole morphology, and absence of haplotype sharing in mitochondrial and nuclear DNA markers, we describe a new species of treefrog from Ranomafana National Park in the southern central east of Madagascar. In its adult stage Boophis narinsi sp. n. is highly similar to its sister species, Boophis majori, but appears to differ in having longer hindlimbs. The genetic divergences between these two species (2.5-3.3% in a fragment of the 16S rRNA gene, depending on fragment length and individual haplotype analyzed) are below the threshold typically characterizing distinct species of anurans. Together with their relatively small and largely overlapping ranges and their sympatric occurrence in Ranomafana National Park, this indicates that they potentially could have originated rather recently by adaptive speciation under parapatric or sympatric conditions. Most studies on amphibian speciation have so far by default assumed vicariant speciation. We suggest that alternative speciation scenarios should be considered in future works and characterize settings in which more reliable assessments of adaptive parapatric or sympatric speciation could be carried out. [ABSTRACT FROM AUTHOR]

Based on daily monitoring around an urban pond in the coastal town of Maroantsetra, from 2003-2011, we provide an analysis of the yearly reproductive activity of the tomato frog (Dyscophus antongilii), a large-sized and prominent red-coloured microhylid frog from north-eastern Madagascar. Frogs were observed all year round but despite the limited climatic seasonality in the region it was possible to identify a high activity period between January-May and a lower activity period between June-December. Freshly laid eggs were found in all months except November, and with highest incidence between January and May, while calling was heard in all months. We found a positive correlation between daily adult counts and minimum air temperature. On the contrary rainfall did not significantly predict activity, although boosts of calling and egg-laying especially in the austral winter were observed after heavy rainfall events. We define D. antongilii in Maroantsetra as a sporadic wet season breeder that reproduces at irregular intervals following heavy rain events. [ABSTRACT FROM AUTHOR]

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Leaf-tailed geckos, genus Uroplatus, are one of the most prominent endemic reptile groups from Madagascar, but the species diversity and diversification of this taxonomic group are not completely understood. Here, we present a phylogenetic reconstruction of the small-sized Uroplatus which are included in the Uroplatus ebenaui group, focusing on the most widespread species of these geckos, Uroplatus phantasticus, which occupies a large mid-altitude distribution range in the eastern rainforests of Madagascar. Our phylogeny is based on DNA sequences of four mitochondrial genes (12S rRNA, 16S rRNA, COI and ND4), with a total of 2 312 base pairs. Partitioned Bayesian analysis confirmed U. malama from south-eastern Madagascar as the most basal representative of the group, followed by U. ebenaui from northern lowlands, and clades containing various undescribed candidate species as well as U. finiavana from Montagne d'Ambre in the north. Within our main targeted species U. phantasticus, the northernmost population from Zahamena (here considered as unconfirmed candidate species) forms the most basal lineage, while the southernmost populations studied from Marolambo, Ranomafana and Kianjavato form a nested clade, suggesting the species has expanded its range southwards undergoing repeated events of isolation and differentiation of lineages. Within the Ranomafana–Kianjavato area, we identified three different lineages, of which the two from Ranomafana are differentiated by 28 mutational steps in a fragment of the ND4 gene and occur on opposing banks of the Namorona River. This result suggests that this relatively small river currently limits dispersal and gene flow in these geckos. However, further downstream the Kianjavato population is more closely related to the population on the opposite side of the Namorona in Ranomafana, indicating that this genetic isolation is not absolute, and the river probably represents only a secondary barrier to gene flow in U. phantasticus. [ABSTRACT FROM AUTHOR]

The geographic and temporal origins of Madagascar's biota have long been in the center of debate. We reconstructed a time-tree including nearly all native nonflying and nonmarine vertebrate clades present on the island, from DNA sequences of two single-copy protein-coding nuclear genes (BDNF and RAG1) and a set of congruent time constraints. Reconstructions calculated with autocorrelated or independent substitution rates over clades agreed in placing the origins of the 31 included clades in Cretaceous to Cenozoic times. The two clades with sister groups in South America were the oldest, followed by those of a putative Asian ancestry that were significantly older than the prevalent clades of African ancestry. No colonizations from Asia occurred after the Eocene, suggesting that dispersal and vicariance of Asian/Indian groups were favored over a comparatively short period during, and shortly after, the separation of India and Madagascar. Species richness of clades correlates with their age but those clades that have a large proportion of species diversity in rainforests are significantly more species-rich. This finding suggests an underlying pattern of continuous speciation through time in Madagascar's vertebrates, with accelerated episodes of adaptive diversification in those clades that succeeded radiating into the rainforests. [ABSTRACT FROM AUTHOR]

How, when, and from where Madagascar's vertebrates arrived on the island is poorly known, and a comprehensive explanation for the distribution of its organisms has yet to emerge. We begin to break that impasse by analyzing vertebrate arrival patterns implied by currently existing taxa. For each of 81 clades, we compiled arrival date, source, and ancestor type (obligate freshwater, terrestrial, facultative swimmer, or volant). We analyzed changes in arrival rates, with and without adjusting for clade extinction. Probability of successful transoceanic dispersal is negatively correlated with distance traveled and influenced by ocean currents and ancestor type. Obligate rafters show a decrease in probability of successful transoceanic dispersal from the Paleocene onward, reaching the lowest levels after the mid-Miocene. This finding is consistent with a paleoceanographic model [Ali JR, Huber M (2010) Nature 463:653-656] that predicts Early Cenozoic surface currents periodically conducive to rafting or swimming from Africa, followed by a reconfiguration to present-day flow 15-20 million years ago that significantly diminished the ability for transoceanic dispersal to Madagascar from the adjacent mainland. [ABSTRACT FROM AUTHOR]

This study provides detailed morphological descriptions of previously unknown tadpoles of the treefrog genus Boophis Tschudi and analyses of habitat preferences of several of these tadpoles in Ranomafana National Park. A total of twenty-two tadpoles determined via DNA barcoding are characterized morphologically herein, fourteen of them for the first time. Twelve of these tadpoles belong to taxonomically undescribed candidate species which in several cases are so far only known from their larval stages. Our data show that the larvae of some of these candidate species occur syntopically yet maintaining a clearly correlated genetic and morphological identity, suggesting that they indeed are true biological and evolutionary species. Tadpoles considered to belong to the "adherent" ecomorphological guild inhabit fast-running waters and their oral disc is commonly to continuously attached to the rocky substrate, supposedly to keep their position in the water current. Some of these species are characterized by the presence of a dorsal gap of papillae and the absence of an upper jaw sheath. This guild includes the tadpoles of the B. albipuncatus group (B. ankaratra, B. schuboeae, B. albipunctatus, B. sibilans, B. luciae), and of the B. mandraka group (B. sambirano and six candidate species related to this species and to B. mandraka). Tadpoles considered belonging to the "suctorial" guild inhabit fast-running waters where they use frequently their oral disc to attach to the substrate. They have an enlarged oral disc without any dorsal gap, including two nominal species (B. marojezensis, B. vittatus), and five candidate species related to B. marojezensis. An ecological analysis of the tadpoles of B. luciae, B. schuboeae and B. marojezensis [Ca51 JQ518198] from Ranomafana National Park did not provide evidence for a clear preference of these tadpoles to the fast flowing microhabitat sections of the stream, although the tadpoles discussed in this study are typically caught in this habitat. [ABSTRACT FROM AUTHOR]

Based on 667 tourist interviews in five protected areas (PAs), carried out between January and September 2008, we assessed the ecotouristic potential of Madagascar's amphibians and reptiles compared with that of other components of its unique fauna. Visitors were best informed about mammals and reptiles, and information levels increased with subsequent visits to Madagascar. In contrast, tourists were not well informed about amphibian diversity. However, 27% of the tourists considered encounters with the Malagasy herpetofauna as a factor for deciding to visit the island, and tourists with high zoological interest were willing to pay higher prices for specialised biodiversity tours in PAs and were positive about increased supply in herpetofauna-related activities. Tourists' income affected travel expenditure, trip length and spending behaviour; a higher total trip budget resulted in a higher number of sites visited, but not in an increased number of PAs visited. We estimated that expenditures in Madagascar by ecotourists who visit PAs amounts to 26–29 million USD per year. Currently, only one-quarter of all Madagascar's leisure tourists visit parks (around 49,000), highlighting the importance of improving and diversifying ecotouristic supplies to attract more tourists to Madagascar's nature reserves. [ABSTRACT FROM AUTHOR]

We report results of a morphological and ecological study on the funnel-mouthed tadpoles of litter frogs in the subgenus Chonomantis, genus Mantidactylus, from Madagascar. The larvae of these riparian frogs are characterized by umbelliform oral discs and absence of well developed keratodonts. Based on specimens identified by DNA barcoding we provide general morphological descriptions for the larvae of all eight nominal species plus two candidate species of Chonomantis, and describe the buccal anatomy of seven species. We detected only minor morphometric differences amongst species in mainly the relative size of the oral disc. In addition we found one candidate species (here named Mantidactylus sp. 59) to be characterized by rudimentary keratodont rows, Mantidactylus brevipalmatus by enlarged lungs, and Mantidactylus aerumnalis by a distinct colour pattern. Ecological data gathered in 30 streams in the Ranomafana area indicated important abundance differences amongst species. Mantidactylus melanopleura and Mantidactylus opiparis, which are the two most widespread species over Madagascar, were also locally most abundant in Ranomafana but interestingly showed no diagnostic morphological differences and fully overlapped in morphometric variables. Microhabitat choice of Chonomantis in Ranomafana was characterized by a clear preference for slow-moving stretches of streams with a substrate of submerged dead leaves. In general Chonomantis tadpoles were thus remarkably similar in their morphology and ecology. Considering the high degree of sympatric occurrence, with up to five species of the subgenus co-occurring along the same stream, this indicates a rather low influence of larval competition in creating selective pressures for specialization in these frogs. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, , 149-183. [ABSTRACT FROM AUTHOR]

The article describes two species of plant-breeding frogs, namely, Guibemantis annulatus and Guibemantis wattersoni, found in southeastern Madagascar. G. annulatus has a great similarity with G. punctatus while G. wattersoni is very similar to G. bicalcaratus. The distinguishing characteristics of the species are detailed particularly their coloration, body size, advertisement calls and genetic differences. Both species thrive only in phytotelms which serve as their breeding place. A description for G. punctatus is provided based on new topotypical material. Also discussed is the identity of G. bicalcaratus and other species.

We describe two new species of semiarboreal frogs from the northern central east coast of Madagascar which occur syntopically, at least on the island of Nosy Boraha. The two species are morphologically closest to Blommersia wittei, but differ in advertisement calls and molecular phylogenetic relationships. One of the new species has a remarkable femoral gland structure, as these are shifted towards the distal part of the thigh, close to the knee joint. The new species are apparently microendemic to a small stretch of Madagascar's east coast and have so far not been found at higher elevations. Since both new species are tolerant of habitat disturbance and occur in anthropogenically altered habitats, such as plantations and villages, we propose an IUCN threat status of Least Concern despite their restricted extent of occurrence. [ABSTRACT FROM AUTHOR]

Nagy, Z. T., Glaw, F. & Vences, M. (2010) Systematics of the snake genera Stenophis and Lycodryas from Madagascar and the Comoros. — Zoologica Scripta, 39, 426–435. Arboreal snakes belonging to the pseudoxyrhophiine genus Stenophis inhabit Madagascar but despite their spectacular appearance, surprisingly little is known about their natural history and systematics. Nonetheless, a close phylogenetic affinity of the genera Stenophis and Lycodryas (the latter genus currently includes a single species from the Comoros) has been hypothesized. Based on recent molecular genetic data, however, the monophyly of Stenophis was challenged. This study aimed at a systematic analysis and taxonomic revision of the genera Stenophis and Lycodryas. On the basis of new molecular genetic and morphological data and analyses, we propose to accommodate these snakes in three monophyletic genera: Lycodryas, Phisalixella and Parastenophis, and to consider Stenophis as a junior synonym of Lycodryas. In the new generic arrangement, the genera can also be well distinguished by morphological characters. On the specific level, Phisalixella tulearensis is resurrected and indications of further, undescribed taxa are revealed. [ABSTRACT FROM AUTHOR]

The article describes a new species of treefrog from southeastern Madagascar, Boophis quasiboehmei sp. n., that is highly similar in external adult morphology, bioacoustics and colouration to Boophis boehmei except for a differentiation in a fragment of the mitochondrial 16S ribosomal (RNA) gene. The reseachers concluded that the differentiation is concordant with the pattern in two nuclear genes showing no haplotype sharing of the new species with B. boehmei and with a consistent difference in tadpole morphology. The Boophis quasiboehmei sp. n. group of treefrogs contains several more cryptic species.

Chytridiomycosis ( Bd) is contributing to amphibian extinctions worldwide but has so far not been detected in Madagascar. The high likelihood for Bd to spread to the island and efface this amphibian diversity and endemism hotspot requires respective conservation policies to be developed. Bd could be introduced by the large number of tourists that visit protected areas; therefore, increasing awareness among tourists and encouraging them to participate in safety measures should be a priority conservation action. However, concerns have been raised that tourists would not be able to distinguish between an amphibian disease harmless to humans and emerging diseases that would imply a danger for human health, invoking a negative image of Madagascar as an ecotourism destination. We evaluated whether informing tourists about this infectious animal disease would cause health scare and diminish trip satisfaction. Based on 659 respondents we found that most ecotourists favored to be informed about Bd and were proactive about participating in prevention measures, refuting previous concerns. [ABSTRACT FROM AUTHOR]

Recent surveys of the herpetofauna in the rainforest of the Forêt d'Ambre Special Reserve, northern Madagascar, revealed a distinctive fossorial microhylid anuran species of the genus Rhombophryne. The new species is characterized by medium size (snout-vent length up to 49 mm in males), a stout body, short legs, and tuberculate skin on dorsal surfaces. It is most similar and closely related to R. testudo from the Sambirano region, but differs mainly by the absence of barbels on the lower lip, a different advertisement call, and a pairwise total sequence divergence of 8.5% the mitochondrial 16S RNA gene. We consider this species to be at particular risk from a conservation perspective because it appears to be endemic to a relatively small area of lowland transitional forest heavily altered by human activities. According to the International Union for Conservation of Nature criteria, its threat status is classified as "Endangered." [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We describe a new treefrog species of the genus Boophis (subgenus Sahona) from eastern Madagascar. Boophis calcaratus sp. nov. is distinguished from other species of the group by the presence of distinct dermal heel tubercles which are especially well developed in females. We also re-examined the type specimens of Boophis hillenii, a species that has not been rediscovered after its description in 1979. According to our analysis this taxon shows no consistent morphological differences to Boophis idae and supposed bioacoustic differences may be explained by two distinct call types in this species, and we thus suggest to consider hillenii as junior synonym of idae. [ABSTRACT FROM AUTHOR]

Background: Functional diversity illustrates the range of ecological functions in a community. It allows revealing the appearance of functional redundancy in communities and processes of community assembly. Functional redundancy illustrates the overlap in ecological functions of community members which may be an indicator of community resilience. We evaluated patterns of species richness, functional diversity and functional redundancy on tadpole communities in rainforest streams in Madagascar. This habitat harbours the world's most species-rich stream tadpole communities which are due to their occurrence in primary habitat of particular interest for functional diversity studies. Results: Species richness of tadpole communities is largely determined by characteristics of the larval habitat (stream structure), not by adult habitat (forest structure). Species richness is positively correlated with a size-velocity gradient of the streams, i.e. communities follow a classical species-area relationship. While widely observed for other taxa, this is an unusual pattern for anuran larvae which usually is expected to be hump-shaped. Along the species richness gradient, we quantified functional diversity of all communities considering the similarity and dissimilarity of species in 18 traits related to habitat use and foraging. Especially species-rich communities were characterised by an overlap of species function, i.e. by functional redundancy. By comparing the functional diversity of the observed communities with functional diversity of random assemblages, we found no differences at low species richness level, whereas observed species-rich communities have lower functional diversity than respective random assemblages. Conclusions: We found functional redundancy being a feature of communities also in primary habitat, what has not been shown before using such a continuous measure. The observed species richness dependent pattern of low functional diversity indicates that communities with low species richness accumulate functional traits randomly, whereas species in species-rich communities are more similar to each other than predicted by random assemblages and therefore exhibit an accumulation of stream-specific functional traits. Beyond a certain species richness level, therefore, stream-specific environmental filters exert influence whereas interspecific competition between species does not influence trait assemblage at any species richness level. [ABSTRACT FROM AUTHOR]

Madagascar's flora and fauna are remarkable both for their diversity and supraspecific endemism. Moreover, many taxa contain large numbers of species with limited distributions. Several hypotheses have been proposed to explain this high level of microendemism, including 1) riverine barrier, 2) mountain refuge, and 3) watershed contraction hypotheses, the latter 2 of which center on fragmentation due to climatic shifts associated with Pliocene/Pleistocene glaciations. The Malagasy leaf chameleon genus Brookesia is a speciose group with a high proportion of microendemic taxa, thus making it an excellent candidate to test these vicariance scenarios. We used mitochondrial and nuclear sequence data to construct a Brookesia phylogeny, and temporal concordance with Pliocene/Pleistocene speciation scenarios was tested by estimating divergence dates using a relaxed-clock Bayesian method. We strongly reject a role for Pliocene/Pleistocene climatic fluctuations in species-level diversification of Brookesia. We also used simulations to test the spatial predictions of the watershed contraction model in a phylogenetic context, independent of its temporal component, and found no statistical support for this model. The riverine barrier model is likewise a qualitatively poor fit to our data, but some relationships support a more ancient mountain refuge effect. We assessed support for the 3 hypotheses in a nonphylogenetic context by examining altitude and species richness and found a significant positive correlation between these variables. This is consistent with a mountain refuge effect but does not support the watershed contraction or riverine barrier models. Finally, we find repeated higher level east-west divergence patterns 1) between the 2 sister clades comprising the Brookesia minima group and 2) within the clade of larger leaf chameleons, which shows a basal divergence between western and eastern/northern sister clades. Our results highlight the central role of phylogeny in any meaningful tests of species-level diversification theories. [ABSTRACT FROM PUBLISHER]

Tropical biotas provide excellent settings in which to explore mechanisms of evolutionary diversification, yet these processes remain poorly understood. Pioneering work on biodiversity patterns and diversification processes in other tropical regions has recently been complemented by studies in Madagascar. Here we review diversity models and diversification mechanisms proposed for the fauna of this island and the perspectives for testing them. Madagascar has a diverse biota that has evolved in isolation, and is characterised by regionally pronounced and locally steep environmental gradients, common patterns of microendemism across taxa and numerous evolutionary radiations. These characteristics establish Madagascar as a promising system for the study of pattern and process in species diversification. [Copyright &y& Elsevier]

We describe Liophidium maintikibo, a new species of pseudoxyrhophiine snake from the dry deciduous forest of Kirindy, western Madagascar. The new species is related to Liophidium therezieni but differs by a lower number of ventral scales and several details of colouration. Its ventral scales have a large central black patch which is missing from the subcaudals. This predominantly black ventral side is similar to that of another enigmatic Malagasy snake, Pararhadinaea melanogaster, for which we here present evidence for two new locality records, Ankarana and Daraina in northern Madagascar. The phylogenetic relationships of P. melanogaster (the sole representative of a monotypic genus) have so far not been clarified. Similarities to Liophidium maintikibo may indicate affinities to Liophidium, but P. melanogaster differs from this new species by a lower number of ventrals, subcaudals, number of maxillary teeth and by a different dorsal colouration. [ABSTRACT FROM AUTHOR]

Abstract: We describe a new species of the pseudoxyrhophiine snake genus Thamnosophis from a dry forest of the karstic massif Tsingy de Bemaraha in central western Madagascar. Thamnosophis mavotenda sp. n. is characterised by 19 dorsal scale rows, 188 ventrals, 110 subcaudals, and by colouration (e.g. yellow head sides). Morphological and molecular phylogenetic data indicate that the species is most closely related to the recently described Thamnosophis martae from the far north of the island which inhabits dry karstic forest and subhumid lowland rainforest. This species pair represents a well-supported example of a sister-group relationship in snakes between northern Madagascar and the Tsingy de Bemaraha plateau, and corroborates preliminary observations in other reptile species. We discuss this finding in the light of recent hypotheses on the biogeographic zonation of Madagascar. [Copyright &y& Elsevier]