Marine introgressions and Andean uplift have driven diversification in neotropical Monkey tree frogs (Anura, Phyllomedusinae).

The species richness in the Neotropics has been linked to environmental heterogeneity and a complex geological history. We evaluated which biogeographic processes were associated with the diversification of Monkey tree frogs, an endemic clade from the Neotropics. We tested two competing hypotheses: the diversification of Phyllomedusinae occurred either in a "south-north" or a "north-south" direction in the Neotropics. We also hypothesized that marine introgressions and Andean uplift had a crucial role in promoting their diversification. We used 13 molecular markers in a Bayesian analysis to infer phylogenetic relationships among 57 species of Phyllomedusinae and to estimate their divergence times. We estimated ancestral ranges based on 12 biogeographic units considering the landscape modifications of the Neotropical region. We found that the Phyllomedusinae hypothetical ancestor range was probably widespread throughout South America, from Western Amazon to Southern Atlantic Forest, at 29.5 Mya. The Phyllomedusines' ancestor must have initially diverged through vicariance, generally followed by jump-dispersals and sympatric speciation. Dispersal among areas occurred mostly from Western Amazonia towards Northern Andes and the South American diagonal of dry landscapes, a divergent pattern from both "south-north" and "north-south" diversification hypotheses. Our results revealed a complex diversification process of Monkey tree frogs, occurring simultaneously with the orogeny of Northern Andes and the South American marine introgressions in the last 30 million years.

There and back again: when and how the world's richest snake family (Dipsadidae) dispersed and speciated across the Neotropical region

Aim The widespread megadiverse Neotropical snake family Dipsadidae occurs in a large range of diverse habitats. Therefore, it represents an excellent model to study the diversification of Neotropical biota. Herein, by generating a time-calibrated species-level phylogeny, we investigate the origin and historical biogeography of Dipsadidae and test if its two main Neotropical subfamilies, Xenodontinae and Dipsadinae, have different geographical origins. Location Neotropical region. Taxon Dipsadidae (Serpentes). Methods We generated a new Bayesian time-calibrated phylogeny based on published sequences from six genes for 344 species, including 287 species of Dipsadidae. We subsequently estimated ancestral areas of distribution by comparing models in BioGeoBEARS: DEC (subset sympatry, narrow vicariance), DIVALIKE (narrow and wide vicariance), BAYAREALIKE (no vicariance and widespread sympatry), also testing jump dispersal. We also estimated shifts in the diversification of this group using BAMM, exploring possible relationships with its historical biogeography. Results The best models show that Dipsadidae likely originated approximately 50 million years ago (mya) in Asia. Dispersal was a fundamental process in its historical biogeography. The DEC model with jump dispersal indicated that this family underwent a range extension from Asia and posterior vicariance of North and Central America ancestors. Both Xenodontinae and Dipsadinae originated in Central America and dispersed to South America during Middle Eocene, but did so to different regions (cis and trans-Andean South America, respectively). Xenodontinae entered cis-Andean South America around 39 mya and jump dispersed to the West Indies around 33 mya, while Dipsadinae entered trans-Andean South America multiple times 20–38 mya. The diversification rate decreased through time, except for a clade within Dipsadinae composed of the Dipsadini tribe and the Atractus and Geophis genera. Main Conclusions Our results show that Dipsadidae has an Asian origin and that the two main Neotropical subfamilies originated in Central America, later dispersing to South America in different time periods. This difference is also reflected in the higher diversification rate for the ‘goo-eaters’ in the Dipsadinae subfamily. The current biogeographical patterns of the family Dipsadidae, the most species-rich snake family in the world, have likely been shaped by complex evolutionary and geological processes such as Eocene land bridges, Andean uplift and the formation of the Panama isthmus.

Climatic niche breadths of the Atlantic Forest snakes do not increase with increasing latitude.

The climatic niche is a central concept for understanding species distribution, with current and past climate interpreted as strong drivers of present and historical-geographical ranges. Our aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing latitude. We also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche breadths. Niche breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species ranges. We implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and latitude. We also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche dimensions. Temperature niche breadths were not related to latitude. Precipitation niche breadths decreased with increasing latitude and presented a high phylogenetic signal, that is, significant phylogenetic niche conservatism. We rejected the tradeoff hypotheses of temperature and precipitation niche breadths. Our results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic Forest. We then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

Advertisement calls of 18 anuran species in the megadiverse Atlantic Forest in southeastern Brazil: review and update.

Advertisement calls constitute the main acoustic signals emitted by frogs during reproductive seasons and are considered species-specific. Currently, many studies explore the advertisement calls in this group, including descriptions, taxonomy status, influence of social and ecological aspects, character displacement and plasticity. Although some patterns are detected in several anuran species, the possible intra and interpopulation variation is not well established for the group. Furthermore, new approaches have been proposed to standardize studies in the area and contribute to the description and interpretation of anuran calls, highlighting the urgency of a literature review. We aimed to review and update the advertisement calls of 18 anurans species from the megadiverse Atlantic Forest of Southeastern Brazil. We analyzed 1612 advertisement calls from 175 males of 18 anuran species recorded in ten communities between September 2018 and March 2019. We reviewed the information available in 23 scientific papers and describe each advertisement call based on recent papers. Our results include the definition of sound type for all species recorded, providing temporal and spectral parameters for each species along different localities, including intra and interpopulation variations. We provide new information on the frequency range (minimum and maximum frequencies) for eight species. A new description of the advertisement and territorial call of Boana bandeirantes is also provided based on our fieldwork observations. We emphasize that many species present interpopulation variance throughout their distribution in the megadiverse Atlantic Forest. We hope this information will contribute to future research on amphibian anuran bioacoustics and natural history.

Environmental and phylogenetic aspects affect in different ways the acoustic niche of a frog community in southeastern Brazil.

One of the most important resources for reproduction in frogs is the acoustic space since the advertisement call, which is mostly used to attract females, may suffer interference when the acoustic space is widely filled. Other important resources are calling sites and adequate climatic conditions. We analyzed herein three dimensions of the acoustic niche of anurans (advertisement calls, calling period, and calling sites). We recorded 11 calling species of frogs in a tropical community. Species richness was negatively related to temperature, and daily activity was positively related to humidity. We also observed a greater niche overlap than expected by chance in calling periods. These results indicate that the climatic conditions should act as an environmental filter, synchronizing the calling period. The calling site was not shared among species, and no clear pattern of substrate use was observed. Regarding the acoustic dimension, we observe a phylogenetic signal in the dominant frequency of advertisement calls. Hierarchical cluster analysis also indicated a congruence between acoustic distances and phylogenetic relationships. Therefore, the dominant frequency of advertisement calls was constrained by phylogenetic relationships, indicating that it affects the partitioning and use of acoustic resources, an important dimension in reproductive activity in anurans.

Climatic niche breadths of the Atlantic Forest snakes do not increase with increasing latitude

The climatic niche is a central concept for understanding species distribution, with current and past climate interpreted as strong drivers of present and historical-geographical ranges. Our aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing latitude. We also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche breadths. Niche breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species ranges. We implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and latitude. We also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche dimensions. Temperature niche breadths were not related to latitude. Precipitation niche breadths decreased with increasing latitude and presented a high phylogenetic signal, that is, significant phylogenetic niche conservatism. We rejected the tradeoff hypotheses of temperature and precipitation niche breadths. Our results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic Forest. We then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

The role of spatial heterogeneity in diversity of squamate reptiles in the Atlantic Forest highlands of southeastern Brazil.

Spatial heterogeneity of vegetation is considered to be one of the most important factors that can influence species richness in a region and, therefore, an important driver for species diversity. Here, we investigate how squamate diversity varies throughout a heterogeneous area in southeastern Atlantic Forest. Our sampling site corresponded to a mosaic of forest and open fields in Curucutu nucleus, Serra do Mar State Park, São Paulo State, Southeastern Brazil. Species diversity varied throughout the mosaic in terms of species composition and relative abundance, with some species being clearly associated with a particular physiognomy. However, a decrease is observed in species richness in forest, after the rarefaction method is applied, showing that when the abundance effect is excluded, only species composition differed between physiognomies. On the other hand, both space and environmental heterogeneity were associated with diversity and distribution of squamates. Our results emphasize the importance of environmental heterogeneity, as well as the influence of the spatial location of the sample units, in structuring squamate diversity in a highland assemblage from the Atlantic Forest.

The role of vicariance and dispersal on the temporal range dynamics of forest vipers in the Neotropical region.

The emergence of the diagonal of open/dry vegetations, including Chaco, Cerrado and Caatinga, is suggested to have acted as a dispersal barrier for terrestrial organisms by fragmenting a single large forest that existed in South America into the present Atlantic and Amazon forests. Here we tested the hypothesis that the expansion of the South American diagonal of open/dry landscapes acted as a vicariant process for forest lanceheads of the genus Bothrops, by analyzing the temporal range dynamics of those snakes. We estimated ancestral geographic ranges of the focal lancehead clade and its sister clade using a Bayesian dated phylogeny and the BioGeoBEARS package. We compared nine Maximum Likelihood models to infer ancestral range probabilities and their related biogeographic processes. The best fitting models (DECTS and DIVALIKETS) recovered the ancestor of our focal clade in the Amazon biogeographic region of northwestern South America. Vicariant processes in two different subclades resulted in disjunct geographic distributions in the Amazon and the Atlantic Forest. Dispersal processes must have occurred mostly within the Amazon and the Atlantic Forest and not between them. Our results suggest the fragmentation of a single ancient large forest into the Atlantic and Amazon forests acting as a driver of vicariant processes for the snake lineage studied, highlighting the importance of the diagonal of open/dry landscapes in shaping distribution patterns of terrestrial biota in South America.

The role of spatial heterogeneity in diversity of squamate reptiles in the Atlantic Forest highlands of southeastern Brazil

Spatial heterogeneity of vegetation is considered to be one of the most important factors that can influence species richness in a region and, therefore, an important driver for species diversity. Here, we investigate how squamate diversity varies throughout a heterogeneous area in southeastern Atlantic Forest. Our sampling site corresponded to a mosaic of forest and open fields in Curucutu nucleus, Serra do Mar State Park, São Paulo State, Southeastern Brazil. Species diversity varied throughout the mosaic in terms of species composition and relative abundance, with some species being clearly associated with a particular physiognomy. However, a decrease is observed in species richness in forest, after the rarefaction method is applied, showing that when the abundance effect is excluded, only species composition differed between physiognomies. On the other hand, both space and environmental heterogeneity were associated with diversity and distribution of squamates. Our results emphasize the importance of environmental heterogeneity, as well as the influence of the spatial location of the sample units, in structuring squamate diversity in a highland assemblage from the Atlantic Forest.

Vicariance and regionalization patterns in snakes of the South American Atlantic Forest megadiverse hotspot

Aim Vicariance has often been invoked to explain bioregionalization patterns in the Neotropics. Using a revised point locality data for endemic species, we aimed to test for the first time the predictions of the vicariance model in shaping biogeographical regions for endemic snakes in the Atlantic Forest (AF) megadiverse hotspot. Location South American Atlantic Forest. Taxon Snakes (Reptilia, Serpentes). Methods To identify the non‐random groups of co‐distributed species, we mapped 21,101 point locality records in a grid cell of 0.5° × 0.5° across the AF, and constructed a presence–absence matrix of endemic species. The two major predictions of vicariance model were tested by Biotic Elements (BE) analysis, searching for groups of significantly co‐distributed species (Biotic Elements) by comparing distances between observed and artificial random ranges, produced under null models from Monte Carlo simulations. We also tested for the occurrence of sister species in different Biotic Elements, and compared our results with previous bioregionalization schemes revealed by other organisms in the AF. Results We recorded 252 species of snakes in the Atlantic Forest, of which 79 (31%) are endemic to this domain. Biotic Elements analysis with endemic species revealed seven clusters of co‐distributed species (BEs) corresponding to biogeographical regions. The significant non‐random clusters of geographical ranges revealed in BE analysis, and the distribution of sister species in different BEs, validated both central predictions of the vicariance model. Main conclusions Snakes defined non‐random biogeographical regions in the Atlantic Forest, and these were congruent with previously identified areas based on other groups of organisms, indicating that general processes influenced geographical ranges across the region. Both central predictions of the vicariance model were valid, indicating that vicariant events must have been important in shaping non‐random clusters of co‐distributed snakes in this biodiversity hotspot, harbouring some of the richest snake faunas on the planet.

Museums and cradles of diversity are geographically coincident for narrowly distributed neotropical snakes

Factors driving the spatial configuration of centres of endemism have long been a topic of broad interest and debate. Due to different eco-evolutionary processes, these highly biodiverse areas may harbour different amounts of ancient and recently diverged organisms (paleo- and neo-endemism, respectively). Patterns of endemism still need to be measured at distinct phylogenetic levels for most clades and, consequently, little is known about the distribution, the age and the causes of such patterns. Here we tested for the presence of centres with high phylogenetic endemism (PE) in the highly diverse Neotropical snakes, testing the age of these patterns (paleo- or neo-endemism), and the presence of PE centres with distinct phylogenetic composition. We then tested whether PE is predicted by topography, by climate (seasonality, stability, buffering and relictualness), or biome size. We found that most areas of high PE for Neotropical snakes present a combination of both ancient and recently diverged diversity, which is distributed mostly in the Caribbean region, Central America, the Andes, the Atlantic Forest and on scattered highlands in central Brazil. Turnover of lineages is higher across Central America, resulting in more phylogenetically distinct PE centres compared to South America, which presents a more phylogenetically uniform snake fauna. Finally, we found that elevational range (topographic roughness) is the main predictor of PE, especially for paleo-endemism, whereas low paleo-endemism levels coincide with areas of high climatic seasonality. Our study highlights the importance of mountain systems to both ancient and recent narrowly distributed diversity. Mountains are both museums and cradles of snake diversity in the Neotropics, which has important implications for conservation in this region.

Museums and cradles of diversity are geographically coincident for narrowly distributed neotropical snakes

Factors driving the spatial configuration of centres of endemism have long been a topic of broad interest and debate. Due to different eco-evolutionary processes, these highly biodiverse areas may harbour different amounts of ancient and recently diverged organisms (paleo- and neo-endemism, respectively). Patterns of endemism still need to be measured at distinct phylogenetic levels for most clades and, consequently, little is known about the distribution, the age and the causes of such patterns. Here we tested for the presence of centres with high phylogenetic endemism (PE) in the highly diverse Neotropical snakes, testing the age of these patterns (paleo- or neo-endemism), and the presence of PE centres with distinct phylogenetic composition. We then tested whether PE is predicted by topography, by climate (seasonality, stability, buffering and relictualness), or biome size. We found that most areas of high PE for Neotropical snakes present a combination of both ancient and recently diverged diversity, which is distributed mostly in the Caribbean region, Central America, the Andes, the Atlantic Forest and on scattered highlands in central Brazil. Turnover of lineages is higher across Central America, resulting in more phylogenetically distinct PE centres compared to South America, which presents a more phylogenetically uniform snake fauna. Finally, we found that elevational range (topographic roughness) is the main predictor of PE, especially for paleo-endemism, whereas low paleo-endemism levels coincide with areas of high climatic seasonality. Our study highlights the importance of mountain systems to both ancient and recent narrowly distributed diversity. Mountains are both museums and cradles of snake diversity in the Neotropics, which has important implications for conservation in this region.

Area and distance from mainland affect in different ways richness and phylogenetic diversity of snakes in Atlantic Forest coastal islands.

AIM: The Theory of Island Biogeography posits that ecological and evolutionary processes regulate species richness of isolated areas. We assessed the influences of an island area and distance from the mainland on species richness, phylogenetic diversity, and phylogenetic composition of snakes on coastal islands. LOCATION: Coastal islands of the megadiverse Atlantic Forest in southeastern Brazil. METHODS: We compiled the species composition of 17 coastal islands in southeastern Brazil. Species richness and phylogenetic diversity were calculated for each island. Phylogenetic composition was measured using principal coordinates of phylogenetic structure. We then employed generalized linear models to test the influence of area and distance from the mainland on the diversity metrics. RESULTS: We found a prominent influence of area on species richness, whereas phylogenetic diversity was more affected by distance from the mainland. Snake clades were distinctly associated with area and distance. The Boidae family was associated with nearer and larger islands, whereas Elapidae was broadly distributed. Distance from the mainland was associated with the distribution of Dipsadidae, whereas Colubridae was influenced by both the area and distance. The Viperidae family attained higher values of phylogenetic diversity in smaller and more remote islands. MAIN CONCLUSIONS: This island system conserved a considerable piece of snake richness from southeastern Brazil, including island endemic species. Area and distance from the mainland were important drivers of snake diversity in the Atlantic Forest coastal islands. However, these predictors affected the different components of diversity in different ways. Phylogenetic composition analysis enables us to understand how basal nodes contributed to high levels of phylogenetic diversity on smaller and farther islands regardless of the decrease in species richness.

Atlas of Brazilian snakes: verified point-locality maps to mitigate the wallacean shortfall in a megadiverse snake fauna

Accurate and detailed species distribution maps are fundamental for documenting and interpreting biological diversity. For snakes, an ecologically diverse group of reptiles, syntheses and detailed data on distribution patterns remain scarce. We present the first comprehensive collection of detailed, voucher-based, point-locality, range maps for all described and documented Brazilian snakes, with the major aim of mitigating the Wallacean shortfall and as a contribution towards a better understanding of this rich, threatened, and poorly studied megadiverse fauna. We recorded a total of 412 snake species in Brazil on the basis of an extensive and verified point-locality database of 163,498 entries and 75,681 unique records (available here as Online Supporting Information). Our results reveal previously undocumented patterns of distribution, sampling effort, richness, and endemism levels, resulting in a more objective view of snake diversity in the Neotropics. Apart from these achievements, we understand that the most relevant and enduring contribution of the present atlas is to stimulate researchers to publish corrections, additions, and new discoveries.

Atlas of Brazilian snakes: verified point-locality maps to mitigate the wallacean shortfall in a megadiverse snake fauna

Accurate and detailed species distribution maps are fundamental for documenting and interpreting biological diversity. For snakes, an ecologically diverse group of reptiles, syntheses and detailed data on distribution patterns remain scarce. We present the first comprehensive collection of detailed, voucher-based, point-locality, range maps for all described and documented Brazilian snakes, with the major aim of mitigating the Wallacean shortfall and as a contribution towards a better understanding of this rich, threatened, and poorly studied megadiverse fauna. We recorded a total of 412 snake species in Brazil on the basis of an extensive and verified point-locality database of 163,498 entries and 75,681 unique records (available here as Online Supporting Information). Our results reveal previously undocumented patterns of distribution, sampling effort, richness, and endemism levels, resulting in a more objective view of snake diversity in the Neotropics. Apart from these achievements, we understand that the most relevant and enduring contribution of the present atlas is to stimulate researchers to publish corrections, additions, and new discoveries.

The complex roles of space and environment in structuring functional, taxonomic and phylogenetic beta diversity of frogs in the Atlantic Forest.

Ecological communities are complex entities that can be maintained and structured by niche-based processes such as environmental conditions, and spatial processes such as dispersal. Thus, diversity patterns may be shaped simultaneously at different spatial scales by very distinct processes. Herein we assess whether and how functional, taxonomic, and phylogenetic beta diversities of frog tadpoles are explained by environmental and/or spatial predictors. We implemented a distance-based redundancy analysis to explore variation in components of beta diversity explained by pure environmental and pure spatial predictors, as well as their interactions, at both fine and broad spatial scales. Our results indicated important but complex roles of spatial and environmental predictors in structuring phylogenetic, taxonomic and functional beta diversities. The pure fine-scales spatial fraction was more important in structuring all beta diversity components, especially to functional and taxonomical spatial turnover. Environmental variables such as canopy cover and vegetation structure were important predictors of all components, but especially to functional and taxonomic beta diversity. We emphasize that distinct factors related to environment and space are affecting distinct components of beta diversity in different ways. Although weaker, phylogenetic beta diversity, which is structured more on biogeographical scales, and thus can be represented by spatially structured processes, was more related to broad spatial processes than other components. However, selected fine-scale spatial predictors denoted negative autocorrelation, which may be revealing the existence of differences in unmeasured habitat variables among samples. Although overall important, local environmental-based processes explained better functional and taxonomic beta diversity, as these diversity components carry an important ecological value. We highlight the importance of assessing different components of diversity patterns at different scales by spatially explicit models in order to improve our understanding of community structure and help to unravel the complex nature of biodiversity.

Patterns, biases and prospects in the distribution and diversity of Neotropical snakes.

Motivation: We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. Main types of variables contained: We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Spatial location and grain: Neotropics, Behrmann projection equivalent to 1° × 1°. Time period: Specimens housed in museums during the last 150 years. Major taxa studied: Squamata: Serpentes. Software format: Geographical information system (GIS). Results: The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. Main conclusions: The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.

Are oral deformities in tadpoles accurate indicators of anuran chytridiomycosis?

We evaluated the use of oral deformities as reliable proxies for determining Batrachochytrium dendrobatidis (Bd) infection in tadpoles of six anuran species of the Atlantic Forest in southeastern Brazil. We examined oral discs of 2156 tadpoles of six species of anurans collected in 2016: Aplastodiscus albosignatus, Boana albopunctata, Boana faber, Scinax hayii, Crossodactylus caramaschii, and Physalaemus cuvieri. Three oral deformities were recognized: lack of keratinization only in upper and/or lower jaw sheaths, lack of keratinization only in upper or lower tooth rows, and both deformities together. A subsample composed of all the individuals possessing oral deformities (N = 195) plus randomly selected individuals without oral deformities (N = 184) were tested for Bd via qPCR. Oral deformities were observed in all six species, but only five were infected with Bd. Since we found that dekeratinization of tooth rows was not associated with the presence of Bd in any of the studied species we used a new proxy (jaw sheaths dekeratinization with or without dekeratinization in tooth rows: JSD-proxy) for Bd detection. Our results showed a nonrandom relationship between Bd infection and JSD-proxy in three species of the family Hylidae. However, the use of JSD-proxy for Bd detection in these species resulted in up to 30.8% false positives and up to 29.3% false negatives. The use of the JSD-proxy in species for which no relationship was found reached 100% of false positives. We conclude that the use of oral dekeratinization as a generalized proxy for Bd detection in tadpoles should not be used as a single diagnosis technique.

Another new and threatened species of lancehead genus Bothrops (Serpentes, Viperidae) from Ilha dos Franceses, Southeastern Brazil.

A new insular species of the genus Bothrops is described from Ilha dos Franceses, a small island off the coast of Espírito Santo State, in southeastern Brazil. The new species differs from mainland populations of B. jararaca mainly by its small size, relative longer tail, relative smaller head length, and relative larger eyes. The new species is distinguished from B. alcatraz, B. insularis and B. otavioi by the higher number of ventral and subcaudal scales, relative longer tail and smaller head. The new species is highly abundant on the island, being nocturnal, semiarboreal, and feeding on small lizards and centipeds. Due its unique and restricted area of occurrence, declining quality of habitat, and constant use of the island for tourism, the new species may be considered as critically endangered.