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Simple Summary: Chromosome changes represent important events in evolution. They may trigger processes of speciation or be the result of phylogenetic diversification. In both cases they can represent discrete evolutionary markers of taxonomic significance. In this contribution, we performed a comparative cytogenetic analysis on several representatives of the Malagasy ground geckos of the genus Paroedura. Our results show that chromosome variability in this genus involves chromosome number, morphology, and the independent differentiation of sex chromosome systems in distinct evolutionary lineages. We also highlight that the taxonomic, genetic and chromosome diversity in Paroedura is still underestimated. We present a comparative chromosome study of several taxa of the Malagasy ground geckos of the Paroedura bastardi and P. picta species groups. We employed a preliminary molecular analysis using a trait of the mitochondrial 16S rRNA gene (of about 570 bp) to assess the taxonomic status of the samples studied and a cytogenetic analysis with standard karyotyping (5% Giemsa solution), silver staining (Ag–NOR staining) and sequential C-banding (C-banding + Giemsa and + fluorochromes). Our results show that all the taxa studied of the P. bastardi group (P. ibityensis, P. rennerae and P. cf. guibeae) have a similar karyotype composed of 2n = 34 chromosomes, with two metacentric pairs (1 and 3) and all other pairs being acrocentric. Chromosome diversification in the P. bastardi group was mainly linked to the diversification of heteromorphic sex chromosome systems (ZZ/ZW) in P. ibityensis and P. rennerae, while no heteromorphic sex chromosome pair was found in P. cf. guibeae. The two taxa investigated of the P. picta species group (here named P. picta and P. cf. picta based on molecular data) showed the same chromosome number of 2n = 36, mostly acrocentric elements, but differed in the number of metacentric elements, probably as a result of an inversion at chromosome pair 2. We highlight that the genus Paroedura is characterized by the independent diversification of heterogametic sex chromosomes in different evolutionary lineages and, similarly to other phylogenetically related gecko genera, by a progressive formation of a biarmed element by means of tandem fusions and inversions of distinct pairs. [ABSTRACT FROM AUTHOR]

Simple Summary: Madagascar is home to diverse ecosystems with many endemic reptiles, many of which are threatened by the increasing loss of their habitat. Unfortunately, while some areas have been relatively well studied, there is a paucity of data in most of them. This knowledge gap hinders efforts to collect scientific information in order to conserve the remaining habitat. We conducted surveys in the Bobaomby Complex, in the northern tip of Madagascar to assess its potential for the creation of a new protected area. We found 42 reptile species of which 39 are endemic and the discovery of many threatened species with restricted range distributions. The findings fill the knowledge gaps on the herpetofauna of the Bobaomby Complex. We recommend the inclusion of the Bobaomby Complex into the network of protected areas of Madagascar. Many studies on reptiles have been conducted across Madagascar but some areas are poorly known in terms of the diversity of reptiles such as the Bobaomby Complex in the northern tip of Madagascar. In February and March 2018, we conducted a biodiversity survey within five sites. This biological survey is to collect scientific information for helping new protected creations. Three main methods were used including pitfall trap, visual and acoustic searching along the transect and refuge examination. In total, we recorded 42 species including 5 chameleons, 8 skinks, 11 geckos, 16 snakes and 2 blinds snake species. All recorded species are endemic to Madagascar except Hemidactylus frenatus, Ebenavia inunguis and Phelsuma abbotti. Rare species known only from a few specimens have been recorded in the Bobaomby Complex: Heteroliodon fohy, Pseudoxyrhopus ambreensis, and Madascincus arenicola. Thirteen species are classified as threatened on the IUCN Red List, of which three are Critically Endangered: Paracontias minimus, Madascincus arenicola, and Paroedura lohatsara; three are Endangered: Heteroliodon fohy, Lycodryas inopinae, and Phisalixella variabilis; and seven are Vulnerable: Brookesia ebenaui, Furcifer petteri, Blaesodactylus boivini, Uroplatus ebenaui, Uroplatus henkeli, Liophidium therezieni and Flexiseps ardouini. Our results reveal the importance of the Bobaomby Complex for conserving reptile diversity and highlight the need to protect it. [ABSTRACT FROM AUTHOR]

Simple Summary: In 2014 and 2020, we conducted research in the Montagne des Français Protected Area. This area is recognized for its remarkable fauna and high rate of endemism. The objective of this study was to prioritize areas and determine the diversity and distribution of herpetofauna species, as well as their conservation status, endemism, and threats. In this study, we compared species richness between two surveys conducted in 2014 and 2020. We found that three species of amphibians and one reptile species had a new distribution. The 2020 survey also discovered Langaha pseudoalluaudi, a snake that has not been observed since 2007. The information gathered from this survey could be of use to site managers in the revision of conservation management plans. The harmonious landscape of Montagne des Français is a protected area in the far north of Madagascar. Our herpetofauna surveys were conducted on the eastern and western slopes according to habitat variations within the massif for 2014 and 2020. Our research updates the herpetofauna species richness, spatial distribution ranges, and ecological guilds within the protected area. We used direct opportunistic observations, systematic refuge examinations, and pitfall traps with drift fences at three sites to sample animals. Nineteen amphibian and fifty reptile species were recorded during this study. Three amphibian species and one reptile species, in addition to the snake Langaha pseudoalluaudi, last recorded in 2007, were discovered at Montagne des Français. Here, we present a database update for the herpetofauna species from Montagne des Français and provide a specific morphological description of the morphospecies considered as a new extension or localized distribution. This new database can help site managers develop new strategic conservation plans in response to habitat modification. [ABSTRACT FROM AUTHOR]

Despite discussions extending back almost 160 years, the means by which Madagascar's iconic land vertebrates arrived on the island remains the focus of active debate. Three options have been considered: vicariance, range expansion across land bridges, and dispersal over water. The first assumes that a group (clade/lineage) occupied the island when it was connected with the other Gondwana landmasses in the Mesozoic. Causeways to Africa do not exist today, but have been proposed by some researchers for various times in the Cenozoic. Over‐water dispersal could be from rafting on floating vegetation (flotsam) or by swimming/drifting. A recent appraisal of the geological data supported the idea of vicariance, but found nothing to justify the notion of past causeways. Here we review the biological evidence for the mechanisms that explain the origins of 28 of Madagascar's land vertebrate clades [two other lineages (the geckos Geckolepis and Paragehyra) could not be included in the analysis due to phylogenetic uncertainties]. The podocnemid turtles and typhlopoid snakes are conspicuous for they appear to have arisen through a deep‐time vicariance event. The two options for the remaining 26 (16 reptile, five land‐bound‐mammal, and five amphibian), which arrived between the latest Cretaceous and the present, are dispersal across land bridges or over water. As these would produce very different temporal influx patterns, we assembled and analysed published arrival times for each of the groups. For all, a 'colonisation interval' was generated that was bracketed by its 'stem‐old' and 'crown‐young' tree‐node ages; in two instances, the ranges were refined using palaeontological data. The synthesis of these intervals for all clades, which we term a colonisation profile, has a distinctive shape that can be compared, statistically, to various models, including those that assume the arrivals were focused in time. The analysis leads us to reject the various land bridge models (which would show temporal concentrations) and instead supports the idea of dispersal over water (temporally random). Therefore, the biological evidence is now in agreement with the geological evidence, as well as the filtered taxonomic composition of the fauna, in supporting over‐water dispersal as the mechanism that explains all but two of Madagascar's land‐vertebrate groups. [ABSTRACT FROM AUTHOR]

Simple Summary: We implemented a molecular and phylogenetic analysis and a comparative karyological investigation with standard and chromosome banding methods on different taxa of the endemic Malagasy velvet geckos of the genus Blaesodactylus. We present the description of the karyotype of three different taxa and a characterization of the chromosomal diversity in the genus. We show the occurrence of karyological variability in the genus Blaesodactylus in terms of chromosome number (2n = 40–42), morphology, chromosome position of loci of NORs, and distribution pattern of heterochromatin. Considering our results together with the available information on evolutionary related gecko species, we hypothesize that the karyotype evolution in Blaesodactylus mostly involved a decrease in the total number of chromosomes and the formation of biarmed elements. We also highlight that similar pathways of chromosomal rearrangements have been previously observed in other geckos, possibly representing a convergent karyotype evolution. We performed a molecular and phylogenetic analysis and a comparative cytogenetic study with standard karyotyping, silver staining (Ag-NOR) and sequential C-banding + Giemsa, + fluorochromes on several Blaesodactylus samples. The phylogenetic inference retrieved two main clades, the first comprises B. victori, B. microtuberculatus and B. boivini, while the second includes B. sakalava, B. antongilensis and B. ambonihazo. The available samples of B. sakalava form two different clades (here named B. sakalava clade A and clade B), which probably deserve a taxonomic re-evaluation. We found a karyological variability in Blaesodactylus in terms of chromosome number (2n = 40–42), morphology, location of NORs, and heterochromatin distribution pattern. Blaesodactylus antongilensis and B. sakalava clade A and B showed a karyotype of 2n = 40 mostly telocentric chromosomes. Pairs 1 and 6 were metacentric in B. sakalava clade A and B, while pair 1 was composed of subtelocentric/submetacentric elements in B. antongilensis. In contrast, B. boivini displayed a karyotype with 2n = 42 only telocentric chromosomes. NORs were on the first chromosome pair in B. boivini, and on the second pair in B. antongilensis. Adding our data to those available from the literature on evolutionarily related species, we highlight that the chromosome diversification in the genus probably proceeded towards a progressive reduction in the chromosome number and the formation of metacentric elements. [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]

Geckos are an excellent group to study the evolution of sex determination, as they possess a remarkable variability ranging from a complete absence of sex chromosomes to highly differentiated sex chromosomes. We explored sex determination in the Madagascar leaf-tail geckos of the genus Uroplatus. The cytogenetic analyses revealed highly heterochromatic W chromosomes in all three examined species (Uroplatus henkeli, U. alluaudi, U. sikorae). The comparative gene coverage analysis between sexes in U. henkeli uncovered an extensive Z-specific region, with a gene content shared with the chicken chromosomes 8, 20, 26 and 28. The genomic region homologous to chicken chromosome 28 has been independently co-opted for the role of sex chromosomes in several vertebrate lineages, including monitors, beaded lizards and monotremes, perhaps because it contains the amh gene, whose homologs were repeatedly recruited as a sex-determining locus. We demonstrate that all tested species of leaf-tail geckos share homologous sex chromosomes despite the differences in shape and size of their W chromosomes, which are not homologous to the sex chromosomes of other closely related genera. The rather old (at least 40 million years), highly differentiated sex chromosomes of Uroplatus geckos can serve as a great system to study the convergence of sex chromosomes evolved from the same genomic region. [ABSTRACT FROM AUTHOR]

Simple Summary: The geckos of the genus Uroplatus include peculiar endemic species to Madagascar. Even though they have been the subject of several morphological and molecular studies, karyological analyses have been performed only on U. phantasticus, leaving the chromosomal diversity of the genus completely unexplored. In this study, we performed a preliminary molecular analysis and a comparative cytogenetic study providing the first karyotype description of eight species of Uroplatus and an assessment of their karyological variability. We found chromosome diversity in the species studied in terms of total chromosome number (2n = 34–38), localization of loci of Nucleolar Organizer Regions (NORs) (alternatively on the 2nd, 6th, 10th or 16th pair), heterochromatin composition and occurrence of heteromorphic sex chromosome pairs. Adding our newly generated data to those available from the literature, we show that in the genus Uroplatus, as well as in a larger group of phylogenetically related gecko genera, chromosome diversification mainly occurred toward a reduction in the chromosome number by means of chromosome fusions and translocation of NOR-bearing chromosomes. We also hypothesize that the diversification of sex chromosome systems occurred independently in different genera. We provide here the first karyotype description of eight Uroplatus species and a characterization of their chromosomal diversity. We performed a molecular taxonomic assessment of several Uroplatus samples using the mitochondrial 12S marker and a comparative cytogenetic analysis with standard karyotyping, silver staining (Ag-NOR) and sequential C-banding + Giemsa, +Chromomycin A3 (CMA3), +4′,6-diamidino-2-phenylindole (DAPI). We found chromosomal variability in terms of chromosome number (2n = 34–38), heterochromatin composition and number and localization of loci or Nucleolar Organizer Regions (NORs) (alternatively on the 2nd, 6th, 10th or 16th pair). Chromosome morphology is almost constant, with karyotypes composed of acrocentric chromosomes, gradually decreasing in length. C-banding evidenced a general low content of heterochromatin, mostly localized on pericentromeric and telomeric regions. Centromeric bands varied among the species studied, resulting in CMA3 positive and DAPI negative or positive to both fluorochromes. We also provide evidence of a first putative heteromorphic sex chromosome system in the genus. In fact, in U. alluaudi the 10th pair was highly heteromorphic, with a metacentric, largely heterochromatic W chromosome, which was much bigger than the Z. We propose an evolutionary scenario of chromosome reduction from 2n = 38 to 2n = 34, by means of translocations of microchromosomes on larger chromosomes (often involving the NOR-bearing microchromosomes). Adding our data to those available from the literature, we show that similar processes characterized the evolutionary radiation of a larger gecko clade. Finally, we hypothesize that sex chromosome diversification occurred independently in different genera. [ABSTRACT FROM AUTHOR]

Large expanses of tropical rainforest have been converted into agricultural landscapes cultivated by smallholder farmers. This is also the case in north‐eastern Madagascar; a region that retains significant proportions of forest cover despite slash‐and‐burn shifting hill rice cultivation and vanilla agroforestry expansion. The region is also a global hotspot for herpetofauna diversity, but how amphibians and reptiles are affected by land‐use change remains largely unknown. Using a space‐for‐time study design, we compared species diversity and community composition across seven prevalent land uses: unburned (old‐growth forest, forest fragment, and forest‐derived vanilla agroforest) and burned (fallow‐derived vanilla agroforest, woody fallow, and herbaceous fallow) land‐use types, and rice paddy. We conducted six comprehensive, time‐standardized searches across at least 10 replicates per land‐use type and applied genetic barcoding to confirm species identification. We documented an exceptional diversity of herpetofauna (119 species; 91% endemic). Observed plot‐level amphibian species richness was significantly higher in old‐growth forest than in all other land‐use types. Plot‐level reptile species richness was significantly higher in unburned land‐use types compared with burned land‐use types. For both amphibians and reptiles, the less‐disturbed land‐use types showed more uneven communities and the species composition in old‐growth forest differed significantly from all other land‐use types. Amphibians had higher forest dependency (38% of species occurred exclusively in old‐growth forest) than reptiles (26%). Our analyses thus revealed that the two groups respond differently to land‐use change: we found less pronounced losses of reptile species richness especially in unburned agricultural habitats, suggesting that reptiles are less susceptible to land‐use change than amphibians, possibly due to their ability to cope with hotter and drier microclimates. In conclusion, our findings emphasize existing conservation opportunities – especially for reptiles – in extensive agricultural landscapes while highlighting the precarious situation of amphibians in disappearing old‐growth forests. [ABSTRACT FROM AUTHOR]

The postcranial skeleton of the gliding neodiapsid reptile Coelurosauravus elivensis (Lower Sakamena Formation, ?upper Permian, southwestern Madagascar) is re-described in detail based on all previously referred specimens. The exquisite preservation of the material provides three-dimensional details of the individual bones, which are missing in the Laurasian weigeltisaurid material. A new skeletal reconstruction of C. elivensis is proposed including the first reconstruction of a weigeltisaurid reptile in lateral view. The re-examination of the material highlights interspecific differences in the postcranium of weigeltisaurids, in particular in the trunk and patagial spars. These animals have long been considered as arboreal and gliding reptiles. However, new information on the postcranium of C. elivensis reveals strong similarities with both extant and extinct quadrupeds specialized for a clinging arboreal lifestyle. Additionally, the presence of an additional phalanx in the fifth digit of the manus is now attested for all weigeltisaurids where this region is preserved. We suggest that this morphology could have allowed weigeltisaurids to grasp their patagium as observed in the extant gliding agamid Draco. Weigeltisaurids are thus the earliest known gliding vertebrates and some of the first tetrapods with an obligatory arboreal lifestyle, but also represent the only known vertebrates with a hyperphalangy aligned with a gliding apparatus. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether the frequently advocated climate-matching species distribution modeling approach could predict the well-characterized colonization of Florida by the Madagascar giant day gecko Phelsuma grandis. Location: Madagascar and Florida, USA. Methods: To determine the climatic conditions associated with the native range of P. grandis, we used native-range presence-only records and Bioclim climatic data to build a Maxent species distribution model and projected the climatic thresholds of the native range onto Florida. We then built an analogous model using Florida presence-only data and projected it onto Madagascar. We constructed a third model using native-range presences for both P. grandis and the closely related parapatric species P. kochi. Results: Despite performing well within the native range, our Madagascar Bioclim model failed to identify suitable climatic habitat currently occupied by P. grandis in Florida. The model constructed using Florida presences also failed to reflect the distribution in Madagascar by overpredicting distribution, especially in western areas occupied by P. kochi. The model built using the combined P. kochi/P. grandis dataset modestly improved the prediction of the range of P. grandis in Florida, thereby implying competitive exclusion of P. grandis by P. kochi from habitat within the former's fundamental niche. These findings thus suggest ecological release of P. grandis in Florida. However, because ecological release cannot fully explain the divergent occupied niches of P. grandis in Madagascar versus Florida, our findings also demonstrate some degree of in situ adaptation in Florida. Main conclusions: Our models suggest that the discrepancy between the predicted and observed range of P. grandis in Florida is attributable to either in situ adaptation by P. grandis within Florida, or a combination of such in situ adaptation and competition with P. kochi in Madagascar. Our study demonstrates that climate-matching species distribution models can severely underpredict the establishment risk posed by non-native herpetofauna. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether the frequently advocated climate- matching species distribution modeling approach could predict the well- characterized colonization of Florida by the Madagascar giant day gecko Phelsuma grandis. Location: Madagascar and Florida, USA. Methods: To determine the climatic conditions associated with the native range of P. grandis, we used native- range presence- only records and Bioclim climatic data to build a Maxent species distribution model and projected the climatic thresholds of the native range onto Florida. We then built an analogous model using Florida presence- only data and projected it onto Madagascar. We constructed a third model using native- range presences for both P. grandis and the closely related parapatric species P. kochi. Results: Despite performing well within the native range, our Madagascar Bioclim model failed to identify suitable climatic habitat currently occupied by P. grandis in Florida. The model constructed using Florida presences also failed to reflect the distribution in Madagascar by overpredicting distribution, especially in western areas occupied by P. kochi. The model built using the combined P. kochi/P. grandis dataset modestly improved the prediction of the range of P. grandis in Florida, thereby implying competitive exclusion of P. grandis by P. kochi from habitat within the former's fundamental niche. These findings thus suggest ecological release of P. grandis in Florida. However, because ecological release cannot fully explain the divergent occupied niches of P. grandis in Madagascar versus Florida, our findings also demonstrate some degree of in situ adaptation in Florida. Main conclusions: Our models suggest that the discrepancy between the predicted and observed range of P. grandis in Florida is attributable to either in situ adaptation by P. grandis within Florida, or a combination of such in situ adaptation and competition with P. kochi in Madagascar. Our study demonstrates that climate- matching species distribution models can severely underpredict the establishment risk posed by non- native herpetofauna. [ABSTRACT FROM AUTHOR]

Madagascar has historically suffered from high fragmentation of forested habitats, often leading to biodiversity loss. Neverthless, forest fragments still retain high levels of biological diversity. The Haute Matsiatra Region (south-eastern Madagascar) hosts the renowned Andringitra National Park and several surrounding isolated forest fragments embedded in a matrix of human-dominated landscape. During a herpetological survey conducted in the Region, we visited a total of 25 sites. We applied a molecular taxonomic approach to identify the collected material and generate new reference sequences to improve the molecular identification of Malagasy herpetofauna. We identified a total of 28 amphibian and 38 squamate taxa and provided a systematic account for each one of them. Nine of the identified taxa are candidate species, amongst which one was newly identified. We extended the known distributional range of 21 taxa (nine amphibians and 12 squamates). Although the largest forest fragments hold a higher number of species, we also detected a relatively high herpetological diversity in small patches. Our results highlight the importance of investigating small forest fragments to contribute to a better understanding of the patterns of diversity and distribution of the amphibians and reptiles of Madagascar. [ABSTRACT FROM AUTHOR]

Altered environments in urban areas are known to impact and change animal behaviour. In particular, artificial light at night (ALAN) affects behaviour across taxonomic groups, including reptiles. Geckos in the genus Phelsuma are predominantly diurnal, but some have been documented to alter their foraging behaviour from a diurnal to nocturnal activity period when they have access to artificial light sources. Herein, we report new observations of six Phelsuma spp. (Andaman day geckos, P. andamanensis; blue‐tailed day geckos, P. cepediana; Madagascar giant day geckos, P. grandis; Réunion ornate day geckos, P. inexpectata; gold dust day geckos, P. laticauda; Mahé day geckos, P. sundbergi longinsulae) using artificial lights to engage in nocturnal activity that includes foraging, courtship, and agonistic behaviour. Artificial light at night augments the amount of time predators, especially visual predators, can spend foraging. This can increase their overall daily activity period (i.e. the amount of time spent active within 24 h), and research is yet to fully understand the cost–benefit trade‐offs this altered behaviour has on individual fitness. Overall, our novel accounts of six Phelsuma spp. contribute to knowledge regarding the diversity of animals that have altered their behaviour in response to ALAN and highlight the behavioural flexibility of this group of geckos. [ABSTRACT FROM AUTHOR]

Characterising species–landscape associations is relevant for conservation planning and management in response to environmental transformation. The occurrence of reptiles is linked to landscape structure that allows for thermoregulation, shelter and feeding, but the relative importance of these factors is unknown for many tropical and subtropical species. We used community‐level occupancy modelling and remote sensing to investigate the effects of vegetation structure and anthropogenic development on reptile occurrence in a Malagasy dry forest during the dry season (June and July). The occupancy estimates for some species revealed that species occupancy increased for more densely vegetated sites situated closer to the forest edge. The proximity of anthropogenic transformation did not significantly affect the occurrence of species except for Uroplatus guentheri which showed preference for sites away from settlements. Because most species and those most sensitive to habitat transformation were associated with edges of intact forest patches with denser green vegetation, these areas should form the focus of efforts to conserve reptiles in tropical dry forests. We also demonstrate how setting and scale can affect how habitat‐use patterns are interpreted and the importance of local, species‐specific studies. [ABSTRACT FROM AUTHOR]

Aim: For 80 years, popular opinion has held that most of Madagascar's terrestrial vertebrates arrived from Africa by transoceanic dispersal (i.e. rafting or swimming). We reviewed this proposition, focussing on three ad hoc hypotheses proposed to render this unlikely scenario more feasible: (a) Could hibernation have helped mammals to reach Madagascar? (b) Could the aquatic abilities of hippopotamuses have enabled them to swim the Mozambique Channel? (c) How valid is the Ali‐Huber model predicting that eastward Palaeogene surface currents allowed rafts to reach Madagascar in 3–4 weeks? Finally, we explored the alternative hypothesis of geodispersal via short‐lived land bridges between Africa and Madagascar. Location: East Africa, Madagascar, Mozambique Channel. Taxa: Fish, amphibians, reptiles, birds, mammals. Methods: We established colonization timeframes using molecular divergence dates estimated for Malagasy vertebrate lineages. We reviewed the likelihood of the "torpid waif" and "swimming hippopotamus" hypotheses, and re‐investigated Ali and Huber's model of Eocene jet‐like currents by tracking particle trajectories in currents simulated using the Institut Pierre‐Simon Laplace Earth System Model. Finally, we summarized recent geological findings from the Mozambique Channel, and used them to compile palaeosedimentological maps using PLACA4D. Results: Madagascar's vertebrate fauna has complex origins. Hibernation is probably an adaptation to Madagascar's hypervariable climate, rather than a facilitator of mammal dispersal. Hippopotamus physiology precludes the ability to cross an oceanic channel deeper than 4 m and hundreds of km wide. The Ali‐Huber model of Palaeogene currents considerably underestimated the time required to cross the Mozambique Channel under simulated palaeogeographic conditions. New geological data indicate the existence of three short‐lived land bridges between Africa and Madagascar at 66–60 Ma, 36–30 Ma and 12–05 Ma. Main conclusion: The three Cenozoic land bridges afford a more grounded hypothesis for the dispersal of Madagascar's extant biota than transoceanic rafting or swimming, although vicariance, island hopping and limited rafting also played a role. [ABSTRACT FROM AUTHOR]

The cranial skeleton of the enigmatic gliding neodiapsid reptile Coelurosauravus elivensis (Lower Sakamena Formation, Lopingian, Southwestern Madagascar) is re-described in detail. All previously referred specimens are re-examined under both direct observations and Reflectance Transformation Imaging. Their exquisite preservation yields detailed three-dimensional information on the outline of individual bones and their osteological relationships, which are missing in the Laurasian remains. In contrast to previous studies, the ontogenetic maturity of all specimens is re-affirmed. Previously unidentified elements of the palate, braincase and mandible are described, and a novel reconstruction is proposed, including the first palatal reconstruction in a weigeltisaurid reptile. C. elivensis has the smallest skull of all weigeltisaurids and differs from other species in its facial ornamentation, parietosquamosal frill and larger anterior maxillary dentition. We also provide extensive comparisons with contemporaneous reptiles, possibly closely related taxa and more recent analogs, as well as a preliminary discussion of the functional anatomy of the peculiar cranial morphology of weigeltisaurids. The cranial skeleton is a truss construction with large orbits and temporal fenestrae. By analogy with extant chamaeleonids, the elongate parietosquamosal frill is associated with an increase in length and diameter of the temporal jaw adductors, resulting in an increased gape and/or bite force and speed. Additionally, the spikes and frills of weigeltisaurids most likely served as a display and defensive structure. [ABSTRACT FROM AUTHOR]

Community-based monitoring (CBM)– programs that integrate community members and their values into biodiversity and/or natural resource monitoring– is an effective tool for conservation. Wide inequities exist in CBM collaboration, and monitoring abilities may vary between collaborators of different backgrounds. Therefore exploring the demographic composition of CBM collaborators, and how demographics shape individual monitoring efficacy, can help improve both diversity in CBM representation and program outcomes. Yet, few studies have focused on CBM collaborator demographics, especially in low-income countries. We implemented a CBM project co-designed by protected area managers and local community members in the geographically, biologically, and culturally diverse Southern Madagascar. The project involved 27 scientists and 83 community members who collectively generated 69,429 observations of birds, mammals, amphibians and reptiles across two years (2917 surveys). Using linear regressions and mixed-effects models, we examined how collaborators' demographics (gender, age, and level of formal education) and their prior amount of biological monitoring experience impacted their efficacy, measured as the number of observed species. For both scientists and community members, monitoring teams with women, despite being underrepresented, on average observed more species than male-only teams. Among community members, age and level of formal education had smaller positive effects on efficacy. Our results suggest that CBM projects should actively engage a broad array of community members, including those with marginalized identities, to provide diverse perspectives. Inclusive initiatives offer both tangible (lower project costs) and intangible (community engagement, education, and enhanced collaboration) benefits for local communities and conservation managers alike. • Community-based monitoring (CBM) can be an effective tool for monitoring biodiversity in Madagascar. • Women were more effective at biodiversity monitoring than men. • Age and amount of formal education had slight positive impacts on monitoring efficacy. • Enhanced collaboration between park management and local communities provides benefits to all stakeholders. • CBM programs should embrace a diverse array of demographics and perspectives. [ABSTRACT FROM AUTHOR]

The genus Matoatoa includes two Malagasy endemic species, M. brevipes and M. spannringi. Due to their cryptic behaviour, the two species are known only from a handful of specimens and have been included in few molecular studies. Here we carried out a molecular barcoding analysis using a fragment of the mitochondrial NADH dehydrogenase subunit 2 (ND2) and the first chromosomal analysis of M. brevipes. The molecular analysis confirmed the identity of the studied samples as M. brevipes. However, the level of genetic divergence (4% uncorrected p-distance) between our samples and other sequences of M. brevipes, suggests previously unrecognised diversity within the species. The karyotype of M. brevipes is composed of 2n = 34 chromosomes: the first pair is metacentric, while all the other pairs are telocentric and gradually decreasing in length (Arm Number, AN = 36). C-banding revealed little evidence of centromeric heterochromatin, while NOR-associated heterochromatin was found on the telomeres of a medium sized telocentric pair. No heteromorphic chromosome pairs were found in the karyotype of the species, suggesting that putative sex chromosomes are at an early stage of differentiation. Karyological comparisons with closely related species were performed with Christinus marmoratus, and representatives of the genera Phelsuma, Ebenavia, Paroedura and Uroplatus. Comparisons across genera suggest that chromosome diversification in this group of geckos probably occurred by means of chromosome fusions and inversions, leading to a reduction of the chromosome number and the formation of biarmed elements in different species. [ABSTRACT FROM AUTHOR]

Aim: Madagascar is renowned for its exceptional species diversity and endemism. The island's mountainous regions are thought to have played a role in lineage and species diversification, but this has yet to be explored across taxonomic groups and a temporal context has not yet been identified. We tested whether montane regions have promoted population divergence in Madagascar's vertebrate fauna and, if so, whether these divergence events were contemporaneous. Location: Moist evergreen forests of Madagascar. Taxa: Small mammals and reptiles. Methods: We analysed mitochondrial DNA data from 20 small‐mammal and five reptile species widely distributed across Madagascar's moist evergreen forests. We used phylogenetic and population genetic analyses to identify major phylogeographic patterns, then used linear regression to determine if the strength of phylogeographic structure is related to taxon, body size or elevation. Finally, we tested whether or not divergence across highlands occurred synchronously in multiple species, and used simulations to assess the power of these analyses to accurately estimate divergence times. Results: We observed a shared phylogeographic pattern across multiple species that suggests Madagascar's northern, central and southern highlands have served as important regions of diversification on Madagascar. This pattern was recovered across taxa with varying body sizes and elevational distributions. We also identified four pulses of divergence between the northern and central highlands since the late Miocene, although simulations suggest that our empirical data cannot recover the number or timing of divergence events with high certainty. Finally, we observed several instances of deep intraspecific genetic splits, suggesting that several of the species we evaluated may represent cryptic species complexes. Main Conclusions: We identified a highland‐driven phylogeographic pattern plus several cases of cryptic endemism and recent speciation, which have important evolutionary and conservation implications. This work presents a new phylogeographic hypothesis for recent diversification on Madagascar, reaffirms the urgent need for continued collection of voucher specimens and illuminates areas of particular importance for safeguarding genetic diversity in one of the world's foremost and threatened biodiversity hotspots. [ABSTRACT FROM AUTHOR]

Much of the global wildlife trade is sourced from biodiversity-rich developing countries. These often have high levels of poverty and habitat loss, particularly in rural areas where many depend on natural resources. However, wildlife collection may incentivize local people to conserve habitats that support their livelihoods. Here we examined the contribution of the commercial collection of live animals to rural livelihoods in Madagascar, one of the world's most important biodiversity hotspots. Using questionnaires, we investigated the prevalence, profitability relative to other livelihood activities and local importance of the trade and its capacity to provide incentives for conservation. Thirteen percent of households were engaged in live animal collection in the study area (∼5% trapped reptiles and amphibians and the remainder trapped invertebrates). This formed part of a diverse livelihood strategy and was more profitable than other activities (in terms of returns per unit of effort), with median earnings of ∼US$100 per season (∼25% of Gross National Income per year). However, trapping was part-time, usually undertaken by poorer members of the community and often perceived as opportunistic, risky and financially unreliable. Further, trappers and nontrappers held similar perceptions regarding conservation, suggesting wildlife trade currently does not incentivize enhanced stewardship of traded species and their habitats. Our study brings together a range of methodologies to present the most comprehensive insights into livelihoods and conservation in poor rural communities involved in the commercial collection of live animals to supply international trade. This improved understanding of the wider socioeconomic dimensions of wildlife trade can inform policy and management interventions for both the threats and opportunities associated with global trade in biodiversity both in Madagascar and more generally. [ABSTRACT FROM AUTHOR]

Physiological or behavioural adjustments are a prerequisite for ectotherms to cope with different thermal environments. One of the world's steepest environmental gradients in temperature and precipitation can be found in southeastern Madagascar. This unique gradient allowed us to study the compensation of thermal constraints in the heliothermic lizard Oplurus quadrimaculatus on a very small geographic scale. The lizard occurs from hot spiny forest to intermediate gallery and transitional forest to cooler rain forest and we investigated whether these habitat differences are compensated behaviourally or physiologically. To study activity skin temperature (as proxy for body temperature) and the activity time of lizards, we attached temperature loggers to individuals in three different habitats. In addition, we calculated field resting costs from field resting metabolic rate to compare energy expenditure along the environmental gradient. We found no variation in activity skin temperature, despite significant differences in operative environmental temperature among habitats. However, daily activity time and field resting costs were reduced by 35% and 28% in the cool rain forest compared to the hot spiny forest. Our study shows that O. quadrimaculatus relies on behavioural mechanisms rather than physiological adjustments to compensate thermal differences between habitats. Furthermore, its foraging activity in open, sun exposed habitats facilitates such a highly effective thermoregulation that cold operative temperature, not energetically expensive heat, presents a greater challenge for these lizards despite living in a hot environment. [ABSTRACT FROM AUTHOR]

The concept of biodiversity conservation relies primarily on protected areas. Yet, protected areas are influenced by the surrounding anthropogenic matrix as degradation of landscapes used by humans also has negative consequences on species within the adjacent protected, non-degraded ecosystems. Increasing the heterogeneity of the anthropogenic landscape has the potential to promote biodiversity conservation in protected and non-protected sites., To find options for reconciling land use and biodiversity conservation, we evaluated reptile diversity of two areas. Both areas contained three types of habitat: cultivated areas, degraded forest and undegraded forest. In one area ( Tsim), a network of hedges surrounding fields provided a variety of possible resources for reptile species. Another area ( Andremba) lacked such landscape elements., In 480 survey walks on 48 transects evenly distributed over two areas, we recorded a total of 24 reptile species, of which 18 occurred in both areas., Perennial plant cover explained the variation in local (per transect) species richness best. Species richness was low along field margins in the cultivated area that lacked hedges and had a perennial plant cover below 20%. It was high in undegraded and degraded forest and along hedges in the cultivated area where perennial plant cover was above 40%., Similarities of reptile assemblages were higher between habitat types in the area structurally enriched with hedges, than in the area lacking such enrichment. In the latter area, beta diversity was largely the result of species losses which could result from impeded movement between habitats., Synthesis and applications. A continuous network of hedges and associated trees and shrubs contribute to the maintenance of reptile biodiversity in dry south-western Madagascar. When present, these interconnected landscape elements enhance habitat suitability of the agriculturally used matrix. They also provide habitat for species of conservation concern. High similarity between assemblages in the area with hedges indicated that movement between habitats was facilitated. We conclude that incorporating hedges in pastures contributes not just to the suitability of the matrix, but also enhances landscape connectivity and thus improves biodiversity conservation in the human-used landscape. [ABSTRACT FROM AUTHOR]

Fish scale geckos ( Geckolepis) are taxonomically poorly resolved, mainly because of the difficulty of applying standard morphological characters to diagnose taxa. Three species, Geckolepis maculata, G. polylepis, and G. typica, are currently recognized from Madagascar and the Comoro Islands. Molecular studies suggested a number of operational taxonomical units within the G. maculata complex, but none of these has been formally described. The Comoran population was described as Geckolepis humbloti Vaillant but later synonymized. Prior to our study, no genetic data and little other information were available for this taxon. We revised the status of G. humbloti using molecular genetics, external morphology, and osteological characters retrieved from 3D skeletal models created using micro-computed tomography (micro-CT). Our results demonstrate that G. humbloti represents a genetic lineage strongly distinct from all other Geckolepis species. It is furthermore distinguished by a combination of external morphological characters and probably by osteology. We therefore resurrect G. humbloti Vaillant, 1887 from synonymy with G. maculata. Remarkably, this lineage is not restricted to the Comoros: A specimen from Tsingy de Bemaraha in western Madagascar falls as a closely related sister lineage to all Comoran Geckolepis in our molecular phylogenetic analysis and is osteologically almost identical with a specimen from the type locality Grand Comoro. We therefore include it in G. humbloti. The phylogenetic topology and the intraspecific genetic divergences suggest that the Comoros were colonized naturally from western Madagascar by overseas dispersal. G. humbloti is not considered as threatened, but its presence is indicative of natural or near-natural habitats. [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]

A new species of proteocephalid cestodes, provisionally assigned to the polyphyletic genus Ophiotaenia La Rue, 1911 (Cestoda: Proteocephalidae), is described from Compsophis infralineatus (Günther) (Serpentes: Pseudoxyrhophiidae) endemic to Madagascar. Ophiotaenia oreae n. sp. differs from all African and Asian species of Ophiotaenia by possessing more uterine diverticula (68–82 on one side). It is also characterised by the absence of an apical organ, the relative sizes of the cirrus-sac and ovary, the almost equatorial position of the gonopore, the diameter of the embryophore, and other biometric characteristics. Phylogenetic relationships of the new species indicate its relatedness to Indomalayan and Australasian proteocephalids from reptiles. Ophiotaenia oreae n. sp. formed a well-supported clade composed of species of Australophiotaenia de Chambrier, Beveridge and Scholz, 2018 from Australian snakes, Macrobothriotaenia ficta (Meggitt, 1931) from Xenopeltis unicolor Reinwardt in Boie from Vietnam, Ophiotaenia sp. from Trimeresurus flavomaculatus (Gray) from the Philippines, and Ophiotaenia bungari de Chambrier, Binh and Scholz, 2012 from Bungarus fasciatus (Schneider) from Vietnam. The only proteocephalid from Madagascan snakes sequenced so far, Ophiotaenia lapata Rambeloson, Ranaivoson and de Chambrier, 2012 from Madagascarophis colubrinus (Schlegel), does not form a monophyletic group with the new species. The actual species diversity of reptilian cestodes in Madagascar is undoubtedly underestimated. Because of the assumed strict (oioxenous) host specificity of reptilian proteocephalids and rich fauna of snakes occurring in Madagascar, it is plausible to expect the existence of dozens new species of proteocephalids on this island. [Display omitted] • A new species of tapeworm from an endemic snake of Madagascar is described. • Phylogenetic relationships of the new species indicate its relatedness to Indomalayan and Australasian tapeworms. • The only species from Malagasy snakes sequenced so far, O. lapata , does not form a monophyletic group with O. oreae n. sp. • The actual species diversity of reptilian cestodes in Madagascar is undoubtedly underestimated. [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 article presents a study which aims to increase the knowledge on the herpetofauna of Nosy Komba, northern Madagascar and help future environmental management to protect the distinct insular fauna and flora. It states that 26 species of reptile and six species of amphibian were discovered in a rapid assessment of the herpetofauna on the offshore island of Nosy Komba. It is inferred that the small island needs tighter protection of its forests in the future.

The article discusses Madagascar's leaf tailed geckos of genus Uroplatus along with the information on geographical distribution, species boundries and high intraspecific genetic variability. It focuses on high intraspecific genetic variability to offer information on future taxonomic revisions, spatial prioritisation of conservation efforts. It mentions 14 species which has been allocated in five species group which include U. ebenaui group, U. alluaudi group and U. lineatus group.

Geophysical evidence strongly supports the complete isolation of India and Madagascar (Indo-Madagascar) by ∼100 million years ago, though sparse terrestrial fossil records from these regions prior to ∼70 million years ago have limited insights into their biogeographic history during the Cretaceous. A new theropod dinosaur, Dahalokely tokana, from Turonian-aged (∼90 million years old) strata of northernmost Madagascar is represented by a partial axial column. Autapomorphies include a prominently convex prezygoepipophyseal lamina on cervical vertebrae and a divided infraprezygapophyseal fossa through the mid-dorsal region, among others. Phylogenetic analysis definitively recovers the species as an abelisauroid theropod and weakly as a noasaurid. Dahalokely is the only known dinosaur from the interval during which Indo-Madagascar likely existed as a distinct landmass, but more complete material is needed to evaluate whether or not it is more closely related to later abelisauroids of Indo-Madagascar or those known elsewhere in Gondwana. [ABSTRACT FROM AUTHOR]

Abstract: Lasasaurus beltanae nov. gen. nov. sp., a new procolophonid (Reptilia, Parareptilia) from the Lower Triassic of Madagascar, is represented by a single partial skeleton preserved in a ferro-calcareous nodule from the Middle Sakamena Formation, in the North of the island. This new taxon is unique in possessing peculiar, fine and dendritic crests running along the posterolateral side of the squamosal, widely spaced maxillary teeth, subparallel mesiodistal ridges connecting maxillary teeth to the tooth row, and a strongly acute anterior margin of the copula (hyoid bone). This well-preserved specimen belongs to a juvenile individual. The inclusion of L. beltanae nov. gen. nov. sp. in a phylogenetic analysis suggests that it is close to Theledectinae, Procolophoninae, and Leptopleurinae, though their respective relationships are uncertain. This specimen is the first procolophonid described from Madagascar and represents a minor terrestrial component of a coastal vertebrate assemblage dominated by amphibious to fully-aquatic taxa. [Copyright &y& Elsevier]

Madagascar is a biodiversity hotspot threatened by habitat loss, which is detrimental to the future survival of forest-dwelling herpetofauna. For conservation purposes, it is essential to determine how species respond to different types of anthropogenic habitat alteration. We conducted standardized field surveys (a variation of visual encounter survey) to assess species richness, abundance and diversity among forest, clear-cut and orchard habitat types in Montagne des Français, north Madagascar. Forest sites proved to be very different from clear-cut and orchard sites with regards to habitat structure. Lizard species richness, abundance and diversity were significantly lower in clear-cut sites, with only 11% of the observed forest diversity recorded. This shift in species occurrence suggests that lizards are particularly sensitive to this type of habitat alteration. Orchard cultivation did not affect lizard species richness to the same extent, as 56% of the observed forest diversity was recorded in this habitat type. Furthermore lizard abundance was significantly higher in orchard habitat. These observations indicate that although anthropogenic activity can have an adverse effect on the lizard fauna of a given site, it will seldom lead to a total loss of diversity as species typical of pristine forest (specialists) are replaced by species adapted to secondary habitats (often generalists). Our results support the contention that anthropogenic habitat alteration can have a strong negative influence on lizard communities. Researchers should continue to identify which species may be lost or become more vulnerable in future (as a result of population decline) in response to anthropogenic habitat alteration. [ABSTRACT FROM AUTHOR]

The article presents the results of a survey of reptiles and amphibians at several lowland habitats along the east coast of Madagascar in 2010. The survey yielded 45 reptiles and 61 amphibians, which totals 106 species. Structural differences between littoral forests and lowland forests appear to cause a difference in the composition of species. The survey shows that the most remarkable records were those of Blaesodactylus antongilensis, Uroplatus lineatus and Mantidactylus majori in the Sahafina forest which comprise important range extensions for the species.

Abstract: Five main conclusions arise from this review of the responses of species to anthropogenic disturbance in Madagascar: First, species’ reactions to anthropogenic disturbance are generally negative, but remain poorly known. Our knowledge is patchy among and within higher taxonomic groups; we are still largely gathering case studies. Second, taxonomic groups vary considerably in which proximate factors are most important. Third, several groups show differing responses within different ecoregions. Whether these differences are consistent across groups requires further testing. Fourth, related species often have divergent reactions to disturbance, even within lower taxonomic groupings (families or genera). Thus, we cannot rely on phylogenetic relatedness or even ecological similarity to infer similarity in responses. Finally, disturbance typically reduces species diversity (especially of native and/or endemic species), but also causes species turnover, typically with forest specialists replaced by grassland generalists, and endemics replaced by non-endemics (including invasives). Given these knowledge gaps, we stress the urgency of applied studies that assess species’ ecology, behaviour and health across disturbance gradients, including purely anthropogenic landscapes. Remaining natural vegetation and protected areas will be unable to preserve Madagascar’s biodiversity under the impact of climatic change; we must understand responses of plants and animals to disturbance in order to create buffer zones and corridors combining secondary, degraded and natural habitats. [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]

Here, we describe a new species of Azendohsaurus from the Middle–Late Triassic of Madagascar, extending the geographical range of a taxon known otherwise only by a single species from Morocco. Although Azendohsaurus has consistently been regarded as an early dinosaur (based on various advanced dental and gnathic features resembling those characterizing certain dinosaur subgroups), the relatively complete skeletal material, now available from Madagascar, argues strongly against its dinosaurian affinities. Rather, the retention of numerous primitive cranial and postcranial features indicates a surprisingly early divergence of Azendohsaurus within Archosauromorpha and an unusual mosaic of characters in this taxon. Features considered diagnostic of Sauropodomorpha thus are inferred to occur homoplastically in at least one clade of nondinosaurian archosauromorphs, indicating a complex evolution and distribution of features traditionally thought to be derived within archosaurs. Azendohsaurus has teeth resembling those of both early sauropodomorph and ornithischian dinosaurs, yet also possesses numerous inarguable basal archosauromorph cranial and postcranial attributes. This highlights the risk of uncritically referring isolated, Middle–Late Triassic (or even later), ‘leaf-shaped’ teeth with denticles to the Dinosauria. Similarly, the occurrence of such teeth in an early diverging archosauromorph indicates that specializations for herbivory originated more frequently within this clade than conventionally assumed. For example, Azendohsaurus and numerous basal sauropodomorph dinosaur taxa share an array of convergently acquired features associated with herbivory, including tooth denticles, expanded tooth crowns, a downturned dentary and the articular located at the ventral margin of the mandible. Some of these features (denticles, expanded crowns and the ventrally deflected articular) are even more widespread among archosauromorphs, including aetosaurs, silesaurs and ornithischian dinosaurs. A downturned dentary also occurs in Trilophosaurus, a taxon further marked by unique specializations for herbivory, including transversely lophate, tricuspid teeth. An array of features associated with herbivory also occurs in rhynchosaurs and certain crocodilians (e.g. Simosuchus). This distribution suggests that craniodental features associated with herbivory were much more pervasive across the archosauromorph clade than previously recognized, possibly evolving at least six to eight times independently. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the dentary and cranial and postcranial material of Trematochampsa oblita from the Late Cretaceous of Madagascar. Trematochampsa oblita is represented by one specimen which comprises of three mandibular fragments and a partial surangular gathered from Upper Cretaceous deposits. Upon comparison with Trematochampsa taqueti, the new material showed the lack of any synapomorphies supporting the generic grouping, thus leading to the erection of a new genus. The presentation of new material has aided the increase of phylogenetic resolution within specific groups of Mesoeucrodylia.

Amphibians and reptiles were surveyed at several rainforest sites on the Tsaratanana Massif and in the nearby Manongarivo Massif, NW Madagascar. Visual methods and pitfalls led to the discovery of 30 amphibian and 23 reptile species at Tsaratanana, and 30 amphibian and 17 reptile species at Manongarivo. The herpetofauna present at the investigated sites turned out to be composed (1) of typical elements of Madagascar's eastern rainforests, (2) of species widely distributed at low altitudes of the northwest, (3) of species typical for rainforests of the northeast and north (Montagne d'Ambre), and (4) of a rather large proportion of possible endemics. Beside many still undescribed species, we found some species of considerable biogeographic interest, such as the snake Pseudoxyrhopus ambreensis and the treefrog Boophis blommersae at Tsaratanana, previously known only from Montagne d'Ambre, which emphasizes a biogeographical link to this northernmost massif. At Manongarivo we also found one still unidentified species of leaf-axil dwelling mantellid frog of the subgenus Pandanusicola, representing the first record of this subgenus from northwestern rainforests. Comparisons of mitochondrial DNA sequences of some selected amphibian species indicate that the populations from Tsaratanana and Manongarivo show no or only a slight differentiation between the two massifs but are often strongly different from conspecific populations, or from their closest relatives, in other regions of Madagascar. Conservation at Tsaratanana should, as a priority, include an increase of field surveys and an integration of local people in the management planning of this huge massif. [ABSTRACT FROM AUTHOR]

The only known skull of the extinct Madagacan giant tortoise Dipsochelys abrupta is redescribed. It is similar to the other extinct Madagascar tortoise, Dipsochelys grandidieri, differing in the width of the vomer, in having a ridge on the occipital condyle, and in lacking diverging articular condyles of the quadrates. [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]

The small tetrapod Candelaria barbouri, from the Middle Triassic of southern Brazil, is the first example of an owenettid procolophonoid outside Africa and Madagascar. Candelaria barbouri was originally described as a primitive procolophonid; however, a re-examination of the holotype, as well as new material, reveals that C. barbouri is in fact the youngest member of the Owenettidae, extending the chronological range of the group by more than 10 million years. The recognition of C. barbouri as an owenettid points to a broader diversity and distribution for owenettids than hitherto thought. In addition, C. barbouri is the first member of the Owenettidae to exhibit temporal fenestrae, a discovery that draws attention to the significance of this feature in 'anapsid' reptiles. [ABSTRACT FROM AUTHOR]

Recently discovered reptile specimens from the "Eotriassic" deposits of Madagascar (Lower Triassic) are reported, adding valuable information to our knowledge of Malagasy faunas and providing additional data on tetrapod survivorship across the Permian–Triassic (P–T) boundary. Four specimens are attributable to the terrestrial procolophonoid Barasaurus besairiei Piveteau 1955, whereas the remainder are referable to the aquatic younginiform family Tangasauridae, including some individuals identifiable as Hovasaurus boulei Piveteau 1926. These specimens represent the geologically youngest tangasaurid and Barasaurus specimens to be described from Madagascar and suggest that these small reptiles passed unaffected through the end Permian mass extinction event, when ~78% of amniote families disappeared. [ABSTRACT FROM AUTHOR]

Focuses on the efforts of Christopher Raxworthy to identify all the reptiles, amphibians, and `herpitiles,' that inhabit Madagascar's forests. Background of Raxworthy's study, the first methodical survey of the island's herp population; His lizardlike bursts of activity; Description of the Raxworthy's working conditions; Rewarding herp finds from researchers.

The article discusses a study on the geographical distribution of Heteroliodan fohy, an aglyphous and terrestrial snake genus endemic to Madagascar. It states that the Heteroliodon fohy, which can be distinguished through its dark brown dorsal coloration, whitish venter, yellowish nuchal band, and whitish upper lip, was only known before from the single type specimen found in the of Montagne des Français. It states that the researchers found an adult specimen in the region of Bobaomby, extreme north of Madagascar on October 25, 2006, in which the characteristics show close resemblance to the holotype. It mentions that the intensive survey produced records that represent only the second known locality for these species and may reveal the northern limit for its distributional range.

This article offers information regarding the various animal species at the Bronx zoo. At 13.5 feet in length, the male Nile crocodile is a sight to behold at the entrance to their limestone cave. It mentions that Madagascar is a haven for amphibians and reptiles and the giant day geeko lives in the temperate forest. The radiated tortoise, a critically endangered species, shares its forest with ring-tailed and collared lemurs. The tomato and mantella frogs use their bright colors to show to would be predators.

Chameleons are well-known, highly distinctive lizards characterized by unique morphological and physiological traits, but their karyotypes and sex determination system have remained poorly studied. We studied karyotypes in six species of Madagascan chameleons of the genus Furcifer by classical (conventional stain, C-banding) and molecular (comparative genomic hybridization, in situ hybridization with rDNA, microsatellite, and telomeric sequences) cytogenetic approaches. In contrast to most sauropsid lineages, the chameleons of the genus Furcifer show chromosomal variability even among closely related species, with diploid chromosome numbers varying from 2n = 22 to 2n = 28. We identified female heterogamety with cytogenetically distinct Z and W sex chromosomes in all studied species. Notably, multiple neo-sex chromosomes in the form Z1Z1Z2Z2/Z1Z2W were uncovered in four species of the genus (F. bifidus, F. verrucosus, F. willsii, and previously studied F. pardalis). Phylogenetic distribution and morphology of sex chromosomes suggest that multiple sex chromosomes, which are generally very rare among vertebrates with female heterogamety, possibly evolved several times within the genus Furcifer. Although acrodontan lizards (chameleons and dragon lizards) demonstrate otherwise notable variability in sex determination, it seems that female heterogamety with differentiated sex chromosomes remained stable in the chameleons of the genus Furcifer for about 30 million years. [ABSTRACT FROM AUTHOR]