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Although non-front fanged snakes account for almost two-thirds of snake diversity, most studies on venom composition and evolution focus exclusively on front-fanged species, which comprise most of the clinically relevant accidents. Comprehensive reports on venom composition of non-front fanged snakes are still scarce for several groups. In this study, we address such shortage of knowledge by providing new insights about the venom composition among species of Phalotris, a poorly studied Neotropical dipsadid genus. Phalotris are known for their specialized venom delivery system and toxic venoms, which can cause life-threatening accidents in humans. We evaluate the venom-gland transcriptome of Phalotris, comparing the following three South American species: P. reticulatus for the Araucaria Pine forests, P. lemniscatus for the Pampa grasslands, and P. mertensi for the Brazilian Cerrado. Our results indicate similar venom profiles, in which they share a high expression level of Kunitz-type inhibitors (KUNZ). On the other hand, comparative analyses revealed substantial differences in the expression levels of C-type lectins (CTL) and snake venom metalloproteinases (SVMP). The diverse set of SVMP and CTL isoforms shows signals of positive selection, and we also identified truncated forms of type III SVMPs, which resemble type II and type I SVMPs of viperids. Additionally, we identified a CNP precursor hosting a proline-rich region containing a BPP motif resembling those commonly detected in viperid venoms with hypotensive activity. Altogether, our results suggest an evolutionary history favoring high expression levels of few KUNZ isoforms in Phalotris venoms, contrasting with a highly diverse set of SVMP and CTL isoforms. Such diversity can be comparable with the venom variability observed in some viperids. Our findings highlight the extreme phenotypic diversity of non-front fanged snakes and the importance to allocate greater effort to study neglected groups of Colubroidea.

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Snake venoms have evolved in several families of Caenophidae, and their toxins have been assumed to be biochemical weapons with a role as a trophic adaptation. However, it remains unclear how venom contributes to the success of venomous species for adaptation to different environments. Here we compared the venoms from Bothrocophias hyoprora, Bothrops taeniatus, Bothrops bilineatus smaragdinus, Bothrops brazili, and Bothrops atrox collected in the Amazon Rainforest, aiming to understand the ecological and toxinological consequences of venom composition. Transcriptomic and proteomic analyses indicated that the venoms presented the same toxin groups characteristic from bothropoids, but with distinct isoforms with variable qualitative and quantitative abundances, contributing to distinct enzymatic and toxic effects. Despite the particularities of each venom, commercial Bothrops antivenom recognized the venom components and neutralized the lethality of all species. No clear features could be observed between venoms from arboreal and terrestrial habitats, nor in the dispersion of the species throughout the Amazon habitats, supporting the notion that venom composition may not shape the ecological or toxinological characteristics of these snake species and that other factors influence their foraging or dispersal in different ecological niches.

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The skull of vipers is a highly kinetic anatomical structure involved in envenomating and consuming of prey. Morphological knowledge about the viperid skull is based on studies on some groups of species, but information on its variation within the whole family and its functional morphology is still scarce. In this study, we aimed to explore variation in skull morphology among species of the three subfamilies of Viperidae, and test whether that variation correlates with macrohabitat and diet. We performed quantitative analyses of the viperid skull based on broad taxonomic sampling and two methodological approaches: linear and geometric morphometrics. The results of both approaches showed that much of the variation lies in differences of shape and relative size of the premaxilla, the nasals, the frontals, and the parietals. The results indicated that phylogeny and size influence the shape of the skull, but we also found evidence of morphological differentiation between arboreal and terrestrial species and in species with mammal specialist diet. Our findings imply that, besides evolutionary allometry and phylogenetic signal, demands of particular diets coupled with use of certain habitats have in part shaped morphological evolution of the viperid skull.

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Crotalines (pitvipers) in the Americas are distributed from southern Canada to southern Argentina, and are represented by 13 genera and 163 species that constitute a monophyletic group. Their phylogenetic relationships have been assessed mostly based on DNA sequences, while morphological data have scarcely been used for phylogenetic inquiry. We present a total-evidence phylogeny of New World pitvipers, the most taxon/character comprehensive phylogeny to date. Our analysis includes all genera, morphological data from external morphology, cranial osteology and hemipenial morphology, and DNA sequences from mitochondrial and nuclear genes. We performed analyses with parsimony as an optimality criterion, using different schemes for character weighting. We evaluated the contribution of the different sources of characters to the phylogeny through analyses of reduced datasets and calculation of weighted homoplasy and retention indexes. We performed a morphological character analysis to identify synapomorphies for the main clades. In terms of biogeography, our results support a single colonization event of the Americas by pitvipers, and a cladogenetic event into a Neotropical clade and a North American/Neotropical clade. The results also shed light on the previously unstable position of some taxa, although they could not sufficiently resolve the position of Bothrops lojanus, which may lead to the paraphyly of either Bothrops or Bothrocophias. The morphological character analyses demonstrated that an important phylogenetic signal is contained in characters related to head scalation, the jaws and the dorsum of the skull, and allowed us to detect morphological convergences in external morphology associated with arboreality.

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The archipelago of Fernando de Noronha (FN) is located in the Equatorial South Atlantic Ocean, at 375 km off the northeastern coast of Brazil. Its endemic vertebrate land fauna is restricted to only six species, and three main hypotheses have been proposed to explain their presence in the archipelago. These hypotheses suggest FN had alternative biogeographic connections with: 1) the West Indies; 2) the South America mainland; or 3) Africa. Here, we evaluate for the first time the phylogenetic position of Amphisbaena ridleyi within the diversity of Amphisbaenia, and we infer the biogeographic processes that explain its presence in FN and its relationship with amphisbaenids from the West Indies. We analyzed a comprehensive multilocus dataset for Amphisbaenidae using maximum likelihood and time-calibrated Bayesian phylogenetic approaches. Based on our time-calibrated tree, we tested different biogeographic scenarios through historical biogeographic analyses. Our phylogenetic results for the high-level relationships of Amphisbaenia can be parenthetically summarized as (Rhineuridae, (Blanidae, (Bipedidae, (Cadeidae, (Trogonophidae, (Amphisbaenidae))))). Nine highly supported groups of species were recovered among the mainland South American amphisbaenids (SAA), whereas two phylogenetically distant groups of species were inferred for the West Indies: 1) WIC01, an Oligocene lineage present in Cuba and Hispaniola, which is the sister group of all other SAA groups; and 2) WIC02, a Miocene lineage that is restricted to southern Hispaniola and is closely related to Am. ridleyi. We estimated two events of transatlantic dispersal of amphisbaenians from Africa to West Indies: the dispersal of Cadeidae during the Middle Eocene, and the dispersal of the ancestor of Amphisbaena during the transition Eocene/Oligocene. These events were likely affected by the North Equatorial and South Equatorial currents, respectively, which have been flowing westwards since the Paleocene. The ancestral cladogenesis of Amphisbaena during the Late Oligocene is likely related to overwater dispersal events, or alternatively can be associated with the fragmentation of GAARlandia, when WIC01 was isolated in the West Indies, while the remaining groups of Amphisbaena diversified throughout the South American continent. During the Late Miocene, the ancestor of WIC02 dispersed from northern South America to the West Indies, while Am. ridleyi dispersed from the same region to FN. The overwater dispersal of WIC02 was driven by the North Brazilian Current and the dispersal of Am. ridleyi was likely influenced by the periodic shifts in direction and strength estimated for the North Equatorial Counter-Current during the Late Miocene.

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Interspecific differences in snake venom compositions can result from distinct regulatory mechanisms acting in each species. However, comparative analyses focusing on identifying regulatory elements and patterns that led to distinct venom composition are still scarce. Among venomous snakes, Bothrops cotiara and Bothrops fonsecai represent ideal models to complement our understanding of the regulatory mechanisms of venom production. These recently diverged species share a similar specialized diet, habitat, and natural history, but each presents a distinct venom phenotype. Here, we integrated data from the venom gland transcriptome and miRNome and the venom proteome of B. fonsecai and B. cotiara to better understand the regulatory mechanisms that may be acting to produce differing venom compositions. We detected not only the presence of similar toxin isoforms in both species but also distinct expression profiles of phospholipases A2 (PLA2) and some snake venom metalloproteinases (SVMPs) and snake venom serine proteinases (SVSPs) isoforms. We found evidence of modular expression regulation of several toxin isoforms implicated in venom divergence and observed correlated expression of several transcription factors. We did not find strong evidence for miRNAs shaping interspecific divergence of the venom phenotypes, but we identified a subset of toxin isoforms whose final expression may be fine-tuned by specific miRNAs. Sequence analysis on orthologous toxins showed a high rate of substitutions between PLA2s, which indicates that these toxins may be under strong positive selection or represent paralogous toxins in these species. Our results support other recent studies in suggesting that gene regulation is a principal mode of venom evolution across recent timescales, especially among species with conserved ecotypes.

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Atractus badius has a long and controversial nomenclatural history due to both its antiquity and the brevity of its original description. This species was described based on two syntypes from Java. Later, a lectotype was designated and the distribution range restricted to the Guiana Shield. Although this species has been repeatedly recorded throughout Amazonia and the Andes, these records have been erroneously assigned to A. badius because of a considerable level of confusion in the literature. We found 13 additional specimens of this poorly known snake, expanding our knowledge on its morphological variability, phylogenetic relationships and distribution. In this paper, we report new localities and data on meristic, morphometric, coloration, scales micro-ornamentation, osteology and hemipenial morphology to A. badius. We also determine the phylogenetic position of A. badius as nested in a composite Guiana Shield clade. In addition, we discuss recent advances on the systematics of Atractus and comment on some 'new arrangements' with respect to previously recognized species groups and available morphological evidence. Finally, we highlight the importance of accurate voucher identification before promoting taxonomic changes or implementing nomenclatural acts derived from new phylogenetic hypotheses, and notably propose the synonymy of the recently described A. pyroni with A. roulei.

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MOTIVATION: Over the past decade, the field of next-generation sequencing (NGS) has seen dramatic advances in methods and a decrease in costs. Consequently, a large expansion of data has been generated by NGS, most of which have originated from RNA-sequencing (RNA-seq) experiments. Because mitochondrial genes are expressed in most eukaryotic cells, mitochondrial mRNA sequences are usually co-sequenced within the target transcriptome, generating data that are commonly underused or discarded. Here, we present MITGARD, an automated pipeline that reliably recovers the mitochondrial genome from RNA-seq data from various sources. The pipeline identifies mitochondrial sequence reads based on a phylogenetically related reference, assembles them into contigs, and extracts a complete mtDNA for the target species. RESULTS: We demonstrate that MITGARD can reconstruct the mitochondrial genomes of several species throughout the tree of life. We noticed that MITGARD can recover the mitogenomes in different sequencing schemes and even in a scenario of low-sequencing depth. Moreover, we showed that the use of references from congeneric species diverging up to 30 million years ago (MYA) from the target species is sufficient to recover the entire mitogenome, whereas the use of species diverging between 30 and 60 MYA allows the recovery of most mitochondrial genes. Additionally, we provide a case study with original data in which we estimate a phylogenetic tree of snakes from the genus Bothrops, further demonstrating that MITGARD is suitable for use on biodiversity projects. MITGARD is then a valuable tool to obtain high-quality information for studies focusing on the phylogenetic and evolutionary aspects of eukaryotes and provides data for easily identifying a sample using barcoding, and to check for cross-contamination using third-party tools.

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Ontogenetic changes in venom composition have been described in Bothrops snakes, but only a few studies have attempted to identify the targeted paralogues or the molecular mechanisms involved in modifications of gene expression during ontogeny. In this study, we decoded B. jararacussu venom gland transcripts from six specimens of varying sizes and analyzed the variability in the composition of independent venom proteomes from 19 individuals. We identified 125 distinct putative toxin transcripts, and of these, 73 were detected in venom proteomes and only 10 were involved in the ontogenetic changes. Ontogenetic variability was linearly related to snake size and did not correspond to the maturation of the reproductive stage. Changes in the transcriptome were highly predictive of changes in the venom proteome. The basic myotoxic phospholipases A2 (PLA2s) were the most abundant components in larger snakes, while in venoms from smaller snakes, PIII-class SVMPs were the major components. The snake venom metalloproteinases (SVMPs) identified corresponded to novel sequences and conferred higher pro-coagulant and hemorrhagic functions to the venom of small snakes. The mechanisms modulating venom variability are predominantly related to transcriptional events and may consist of an advantage of higher hematotoxicity and more efficient predatory function in the venom from small snakes.

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South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.(AU)

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South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.

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Abstract South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.

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We describe a new species of pitviper of the genus Bothrops from the Peruvian Pampas del Heath, in the Bahuaja-Sonene National Park. Pampas del Heath is an area of seasonally flooded savannas and a northwestern extension of the Gran Chaco Boliviano-Paraguayo. The new species is easily distinguished from its congeners by the exclusive combination of dorsal color pattern of body consisting of small C-shaped blotches, postocular stripe originating posteriorly to the eye, covering posterior supralabials, dorsum of the head with paired markings arranged symmetrically, venter cream heavily speckled with brown, prelacunal scale discrete in contact with second supralabial, three to five prefoveals, subfoveal single usually present, postfoveals absent to two, canthals two, seven intersupraoculars, one or two suboculars, two or three postoculars, seven or eight supralabials, nine to eleven infralabials, 26-27 interrictals, 23-25 middorsal scales, 172 ventrals in the female and 169-173 in males, 45 subcaudals in the female and 50 in males. We performed separate and combined phylogenetic analyses based on morphology and five mitochondrial genes and recovered the new species as a member of the Bothrops neuwiedi species group. All lineages of this clade inhabit the South American dry diagonal. This novel species of pitviper increases the known diversity of the genus Bothrops and adds to the number of described taxa from the unique and scarcely known ecosystem of Pampas del Heath.

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Caenophidian snakes include the file snake genus Acrochordus and advanced colubroidean snakes that radiated mainly during the Neogene. Although caenophidian snakes are a well-supported clade, their inferred affinities, based either on molecular or morphological data, remain poorly known or controversial. Here, we provide an expanded molecular phylogenetic analysis of Caenophidia and use three non-parametric measures of support-Shimodaira-Hasegawa-Like test (SHL), Felsentein (FBP) and transfer (TBE) bootstrap measures-to evaluate the robustness of each clade in the molecular tree. That very different alternative support values are common suggests that results based on only one support value should be viewed with caution. Using a scheme to combine support values, we find 20.9% of the 1265 clades comprising the inferred caenophidian tree are unambiguously supported by both SHL and FBP values, while almost 37% are unsupported or ambiguously supported, revealing the substantial extent of phylogenetic problems within Caenophidia. Combined FBP/TBE support values show similar results, while SHL/TBE result in slightly higher combined values. We consider key morphological attributes of colubroidean cranial, vertebral and hemipenial anatomy and provide additional morphological evidence supporting the clades Colubroides, Colubriformes, and Endoglyptodonta. We review and revise the relevant caenophidian fossil record and provide a time-calibrated tree derived from our molecular data to discuss the main cladogenetic events that resulted in present-day patterns of caenophidian diversification. Our results suggest that all extant families of Colubroidea and Elapoidea composing the present-day endoglyptodont fauna originated rapidly within the early Oligocene-between approximately 33 and 28 Mya-following the major terrestrial faunal turnover known as the "Grande Coupure" and associated with the overall climate shift at the Eocene-Oligocene boundary. Our results further suggest that the caenophidian radiation originated within the Caenozoic, with the divergence between Colubroides and Acrochordidae occurring in the early Eocene, at ~ 56 Mya.

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Elucidating the molecular mechanisms underlying snake venom variability provides important clues for understanding how the biological functions of this powerful toxic arsenal evolve. We analyzed in detail individual transcripts and venom protein isoforms produced by five specimens of a venomous snake (Bothrops atrox) from two nearby but genetically distinct populations from the Brazilian Amazon rainforest which show functional similarities in venom properties. Individual variation was observed among the venoms of these specimens, but the overall abundance of each general toxin family was conserved both in transcript and in venom protein levels. However, when expression of independent paralogues was analyzed, remarkable differences were observed within and among each toxin group, both between individuals and between populations. Transcripts for functionally essential venom proteins ("core function" proteins) were highly expressed in all specimens and showed similar transcription/translation rates. In contrast, other paralogues ("adaptive" proteins) showed lower expression levels and the toxins they coded for varied among different individuals. These results provide support for the inferences that (a) expression and translational differences play a greater role in defining adaptive variation in venom phenotypes than does sequence variation in protein coding genes and (b) convergent adaptive venom phenotypes can be generated through different molecular mechanisms. SIGNIFICANCE: Analysis of individual transcripts and venom protein isoforms produced by specimens of a venomous snake (Bothrops atrox), from the Brazilian Amazon rainforest, revealed that transcriptional and translational mechanisms contribute to venom phenotypic variation. Our finding of evidence for high expression of toxin proteins with conserved function supports the hypothesis that the venom phenotype consists of two kinds of proteins: conserved "core function" proteins that provide essential functional activities with broader relevance and less conserved "adaptive" proteins that vary in expression and may permit customization of protein function. These observations allowed us to suggest that genetic mechanisms controlling venom variability are not restricted to selection of gene copies or mutations in structural genes but also to selection of the mechanisms controlling gene expression, contributing to the plasticity of this important phenotype for venomous snakes.

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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.

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BACKGROUND: Efficient venom delivery systems are known to occur only in varanoid lizards and advanced colubroidean snakes among squamate reptiles. Although components of these venomous systems might have been present in a common ancestor, the two lineages independently evolved strikingly different venom gland systems. In snakes, venom is produced exclusively by serous glands in the upper jaw. Within the colubroidean radiation, lower jaw seromucous infralabial glands are known only in two distinct lineages-the basal pareatids and the more advanced Neotropical dipsadines known as "goo-eating snakes". Goo-eaters are a highly diversified, ecologically specialized clade that feeds exclusively on invertebrates (e.g., gastropod molluscs and annelids). Their evolutionary success has been attributed to their peculiar feeding strategies, which remain surprisingly poorly understood. More specifically, it has long been thought that the more derived Dipsadini genera Dipsas and Sibynomorphus use glandular toxins secreted by their infralabial glands to extract snails from their shells. RESULTS: Here, we report the presence in the tribe Dipsadini of a novel lower jaw protein-secreting delivery system effected by a gland that is not functionally related to adjacent teeth, but rather opens loosely on the oral epithelium near the tip of the mandible, suggesting that its secretion is not injected into the prey as a form of envenomation but rather helps control the mucus and assists in the ingestion of their highly viscous preys. A similar protein-secreting system is also present in the goo-eating genus Geophis and may share the same adaptive purpose as that hypothesized for Dipsadini. Our phylogenetic hypothesis suggests that the acquisition of a seromucous infralabial gland represents a uniquely derived trait of the goo-eating clade that evolved independently twice within the group as a functionally complex protein-secreting delivery system. CONCLUSIONS: The acquisition by snail-eating snakes of such a complex protein-secreting system suggests that the secretion from the hypertrophied infralabial glands of goo-eating snakes may have a fundamental role in mucus control and prey transport rather than envenomation of prey. Evolution of a functional secretory system that combines a solution for mucus control and transport of viscous preys is here thought to underlie the successful radiation of goo-eating snakes.

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Inferring the evolutionary and biogeographic history of taxa occurring in a particular region is one way to determine the processes by which the biodiversity of that region originated. Tree boas of the genus Corallus are an ancient clade and occur throughout Central and South America and the Lesser Antilles, making it an excellent group for investigating Neotropical biogeography. Using sequenced portions of two mitochondrial and three nuclear loci for individuals of all recognized species of Corallus, we infer phylogenetic relationships, present the first molecular analysis of the phylogenetic placement of the enigmatic C. cropanii, develop a time-calibrated phylogeny, and explore the biogeographic history of the genus. We found that Corallus diversified within mainland South America, via over-water dispersals to the Lesser Antilles and Central America, and via the traditionally recognized Panamanian land bridge. Divergence time estimates reject the South American Caribbean-Track as a general biogeographic model for Corallus and implicate a role for events during the Oligocene and Miocene in diversification such as marine incursions and the uplift of the Andes. Our findings also suggest that recognition of the island endemic species, C. grenadensis and C. cookii, is questionable as they are nested within the widely distributed species, C. hortulanus. Our results highlight the importance of using widespread taxa when forming and testing biogeographic hypotheses in complex regions and further illustrate the difficulty of forming broadly applicable hypotheses regarding patterns of diversification in the Neotropical region.

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We present a phylogenetic analysis of the New World dipsadids based on an expanded data matrix that includes 246 terminal taxa including 196 dipsadids. The species are sampled for eight genes (12S, 16S, cytb, nd2, nd4, bdnf, c-mos, rag2). The data are explored using two distinct optimality procedures-maximum parsimony and maximum likelihood-and two alignment strategies-dynamic homology and static homology. Two previously unsampled dipsadid genera, Sordellina and Rhachidelus, are now included in the analysis. The definitions of the genera, Erythrolamprus, Clelia, Hypsirhynchus, Philodryas and Phimophis, and the tribes Alsophiini, Echinantherini and Conophiini, are revised. In order to maintain monophyly, the genus Umbrivaga is synonymized with Erythrolamprus, and two new genera are erected to accommodate Phimophis iglesiasi and Clelia rustica, as well as their closely related species. The West Indian genera Schwartzophis, Darlingtonia, Antillophis and Ocyophis are resurrected. © The Willi Hennig Society 2012.