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1.
Acta Trop ; 241: 106895, 2023 May.
Article in English | MEDLINE | ID: mdl-36931336

ABSTRACT

Lachesis acrochorda envenomation has a lethality rate of approximately 90%. Despite its high lethality, little is known about its local and systemic effects and its relationship with its protein content. Thus, to increase knowledge of L. acrochorda snake venom from the Southwestern ecoregion of Colombia, we developed a proteomic analysis using a "bottom-up shotgun proteomic profiling" approach. Besides, we evaluated toxinological properties and compared the effects with the Bothrops asper snake venom activities. The RP-HPLC profile showed similarities with the L. acrochorda snake venom from the Northwestern ecoregion of Colombia. However, the results displayed differences in the protein families identified, probably due to the proteomic identification strategy. The in vitro and in vivo tests showed a L. acrochorda snake venom with Phospholipase A2 and metalloproteinase activities related to myotoxic, edematic, and hemorrhagic effects. Nevertheless, the L. acrochorda snake venom displayed a low lethality despite a large amount of inoculated venom. This investigation's results will help us improve the knowledge about the relationship between the clinical manifestations of L. acrochorda envenomation and the venom protein content.


Subject(s)
Proteomics , Viperidae , Animals , Humans , Colombia , Snake Venoms , Hemorrhage
2.
PeerJ ; 10: e12765, 2022.
Article in English | MEDLINE | ID: mdl-35186452

ABSTRACT

A new species of Diasporus is described from the lowlands of southwestern Colombia. The new species exhibits a yellowish coloration in life, a character that it shares with other three species in the genus-Diasporus citrinobapheus, D. gularis, and D. tigrillo. The new species differs from all other congeners in having two chrome orange spots (=glandlike protrusions) on sacral region, smooth ventral skin, basal webbing between the toes, and distal papillae at tips of disc covers on fingers II-IV and toes II-IV. Further, the new species differs from all congeners by an uncorrected p-distance of > 5.56% of the 16S rRNA gene fragment examined. In addition to the new species described herein, we demonstrated that the possession of a yellowish coloration in life optimizes unambiguously as a synapomorphy of a clade within Diasporus, which may be recognized as the Diasporus diastema species group. We also discussed the phylogenetic significance of two morphological characters previously considered of systematic value in Diasporus, the occurrence of oval palmar tubercles (undivided) and longitudinal folds (of the vocal sacs) on the throat. On this basis, we demonstrated that these characters appear to be symplesiomorphies rather than synapomorphies of Diasporus. Regarding pointed disc covers (ungual flap) present in some species of Diasporus, we show that this character conflates various characters, involving variation in pad shape, dorsal outline of the disc (ungual flap), and dependence between discs of different digits. Finally, considering that phenotypic data are a valuable source of evidence in testing phylogenetic hypotheses of terraranan frogs, we encourage future research to incorporate phenotypic evidence into phylogenetic studies involved in the genus Diasporus.


Subject(s)
Anura , Intercellular Junctions , Animals , RNA, Ribosomal, 16S , Anura/genetics , Phylogeny , Colombia
3.
Biochimie ; 194: 19-27, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34923046

ABSTRACT

Bothrops asper envenoming is a public health problem in tropical regions of Latin America. Bothrops asper has spread until Gorgona Island in the Pacific Colombian Ocean, but its biochemical venom characterization is poorly known. Thus, to increase knowledge on Bothrops species venoms, we developed for the first time the proteomic analysis using a shotgun approach and performed functional evaluations relevant to its toxicity and compared with two Colombian Southwest ecoregions from the Pacific and Western sides. Besides, we evaluated two antivenoms produced in Colombia (INS and PROBIOL) against three B. asper venom ecoregions through the ELISA approach and first-generation antivenom against B. asper from Gorgona Island. The protein components of B. asper from Gorgona Island were assigned to nine known protein families, sharing a conserved compositional pattern with B. asper from the pacific ecoregion. The RP-HPLC and in vitro activity suggest a phenotypic congruence in the expression of PLA2s and metalloproteinases between the B. asper snake venom from Gorgona Island and pacific, but inversely to the Western ecoregion. Additionally, the antivenoms immunoreactivity against the three B. asper lineage venoms was different. The INS displayed higher titers than PROBIOL against all the venoms and exhibited the most effective immunocapturing capacity against the individual components of snake venom from Gorgona Island. The results of this investigation suggest that B. asper from Gorgona Island displayed similar clinical manifestations concerning the Pacific ecoregion, and the immunoreactivity by antivenoms could be used after B. asper envenomation in Gorgona Island, using one of them preferably.


Subject(s)
Bothrops , Crotalid Venoms , Animals , Bothrops/metabolism , Colombia , Humans , Proteomics , Snake Venoms
4.
Zookeys ; 1057: 185-208, 2021.
Article in English | MEDLINE | ID: mdl-34552372

ABSTRACT

We describe a new species of Leucostethus from Gorgona Island, a small (13 km2) island located 35 km from the Pacific coast of southern Colombia. The new species most resembles L.argyrogaster and L.fugax from western Amazonia at 340-870 m elev. in Peru and Ecuador, with which it shares pale ventral coloration and orange suffusion of the axilla, groin and concealed surfaces of the hind limb, but it is most closely related to L.bilsa from ca. 340 km SW in the southern Chocó at 420-515 m elev., northwestern Ecuador. We report miniscule white spots on the posteroventral surface of the thighs of the new species and, on the basis of our preliminary assessment of their taxonomic distribution, hypothesize that their presence is a synapomorphy of Dendrobatoidea with subsequent losses in a few groups. Given the apparent restriction of the new species to Gorgona Island, it is Vulnerable according to IUCN Red List criteria. In addition to naming the new species, we also propose the following new combinations: L.alacris (Rivero and Granados-Díaz, 1990) comb. nov., L.dysprosium (Rivero and Serna, 2000) comb. nov., and L.yaguara (Rivero and Serna, 1991) comb. nov.

5.
Anat Rec (Hoboken) ; 304(10): 2264-2278, 2021 10.
Article in English | MEDLINE | ID: mdl-34436828

ABSTRACT

Liotyphlops is a genus of blindsnakes distributed in Central and South America. We reviewed specimens of Liotyphlops albirostris along its current distribution range and, based on morphological data and ecological niche modeling analyses, we restrict the geographical range of L. albirostris and validate three previously described species. In this revision, we describe the morphological variation in the populations from Panamá, Colombia, Ecuador, and Venezuela, and propose a new taxonomic arrangement. We revalidate three previous synonyms of L. albirostris to full species status, while dividing the populations from Colombia in two subspecies-one attributed to a previously recognized species from the Caribbean region, and a new one from the Andean region. The new species differs from L. albirostris from Panamá in cephalic scale arrangements that effectively reduces the previously reported variability of these scales in L. albirostris. We also explore some osteological differences that are congruent with the variation observed. We hope that the recognition of these new species better represents the diversity within Liotyphlops, helping to bring these new species out of their cryptic status so that they will be considered in future conservation efforts.


Subject(s)
Osteology , Snakes , Animals , Ecosystem , Geography , Snakes/classification , South America
6.
Mol Ecol ; 29(11): 1944-1956, 2020 06.
Article in English | MEDLINE | ID: mdl-31971303

ABSTRACT

Hybridization and introgression can have complex consequences for both species evolution and conservation. Here, we investigated the origin and characteristics of a putative hybrid zone between two South American poison dart frog species, Oophaga anchicayensis and the critically endangered Oophaga lehmanni, which are heavily sought after on the illegal pet market. Using a combination of phenotypic (49 traits) and genomic (ddRADseq) data, we found that the putative hybrids are morphologically distinct from their parental species and confirmed genomic signatures of admixture in these populations. Several lines of evidence (hybrid indices, interspecific hybrid heterozygosity, genomic clines, comparisons with simulated hybrids and demographic modelling) support the conclusion that these populations are not comprised of early-generation hybrids and thus, they probably did not arise as a result of illegal translocations associated with wildlife trafficking. Instead, they probably represent an independent lineage which has persisted through isolation and has only relatively recently re-established gene flow with both parental species. Furthermore, we detected signals of differential introgression from parental species into these hybrid populations which suggest relaxed stabilizing selection on these aposematic colour morphs, potentially via context-dependent female choice. These populations thus provide a fascinating window into the role of hybridization, isolation and female choice in the diversification of South American poison dart frogs. In addition, our results underline the importance of landscape conservation measures to protect, not only known localities of nominal species, but also the phenotypic and genomic variation harbored by admixed lineages which represent crucial repositories for the impressive diversity in this system.


Subject(s)
Anura/genetics , Gene Flow , Hybridization, Genetic , Animals , Anura/classification , Endangered Species , Female , Phenotype , South America
7.
PeerJ ; 7: e6115, 2019.
Article in English | MEDLINE | ID: mdl-30627486

ABSTRACT

The complex geological history of Central America has been useful for understanding the processes influencing the distribution and diversity of multiple groups of organisms. Anurans are an excellent choice for such studies because they typically exhibit site fidelity and reduced movement. The objective of this work was to identify the impact of recognized geographic barriers on the genetic structure, phylogeographic patterns and divergence times of a wide-ranging amphibian species, Hyalinobatrachium fleischmanni. We amplified three mitochondrial regions, two coding (COI and ND1) and one ribosomal (16S), in samples collected from the coasts of Veracruz and Guerrero in Mexico to the humid forests of Chocó in Ecuador. We examined the biogeographic history of the species through spatial clustering analyses (Geneland and sPCA), Bayesian and maximum likelihood reconstructions, and spatiotemporal diffusion analysis. Our data suggest a Central American origin of H. fleischmanni and two posterior independent dispersals towards North and South American regions. The first clade comprises individuals from Colombia, Ecuador, Panama and the sister species Hyalinobatrachium tatayoi; this clade shows little structure, despite the presence of the Andes mountain range and the long distances between sampling sites. The second clade consists of individuals from Costa Rica, Nicaragua, and eastern Honduras with no apparent structure. The third clade includes individuals from western Honduras, Guatemala, and Mexico and displays deep population structure. Herein, we synthesize the impact of known geographic areas that act as barriers to glassfrog dispersal and demonstrated their effect of differentiating H. fleischmanni into three markedly isolated clades. The observed genetic structure is associated with an initial dispersal event from Central America followed by vicariance that likely occurred during the Pliocene. The southern samples are characterized by a very recent population expansion, likely related to sea-level and climatic oscillations during the Pleistocene, whereas the structure of the northern clade has probably been driven by dispersal through the Isthmus of Tehuantepec and isolation by the Motagua-Polochic-Jocotán fault system and the Mexican highlands.

8.
Anat Rec (Hoboken) ; 302(7): 1074-1092, 2019 07.
Article in English | MEDLINE | ID: mdl-30471212

ABSTRACT

In recent years, major changes have been proposed for the phylogenetic relationships within the Gymnophthalmoidea, including the description of Alopoglossidae. Recent studies relied primarily on molecular data and have not accounted for evidence from alternative sources, such as morphology. In this study, we provide a detailed bone-by-bone description of the skull of Ptychoglossus vallensis and compare this species with other gymnophthalmoideans. The description was based on 10 cleared-and-stained specimens, four disarticulated skulls, and computed microtomography data of P. vallensis. Most recent phylogenetic hypothesis for the Gymnophthalmoidea was used as a framework to compare the skull of P. vallensis with other species of the Alopoglossidae, Gymnophthalmidae, and Teiidae. Marked similarities between alopoglossids and gymnophthalmids were observed in contrast to teiids, probably due to convergence generated by miniaturization. We also qualitatively analyzed the kinesis of the skull of P. vallensis concluding that is highly akinetic, a trait commonly evolved in fossorial, primarily burrowing squamates. We also describe one unique osteological feature for Alopoglossidae that is not known in any other squamate group. Anat Rec, 302:1074-1092, 2019. © 2018 Wiley Periodicals, Inc.


Subject(s)
Biological Variation, Population , Lizards/anatomy & histology , Skull/anatomy & histology , Animals , Lizards/classification , Phylogeny , Skull/diagnostic imaging , X-Ray Microtomography
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