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1.
Mol Phylogenet Evol ; 197: 108083, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38679303

RESUMO

Kinosternon is the most speciose genus of extant turtles, with 22 currently recognized species, distributed across large parts of the Americas. Most species have small distributions, but K. leucostomum and K. scorpioides range from Mexico to South America. Previous studies have found discordance between mitochondrial and nuclear phylogenies in some kinosternid groups, with the current taxonomy following the nuclear-based results. Herein, based on extended molecular, geographic, and taxonomic sampling, we explore the phylogeographic structure and taxonomic limits for K. leucostomum and the K. scorpioides group and present a fossil-calibrated nuclear time tree for Kinosternon. Our results reveal contrasting differentiation patterns for the K. scorpioides group and K. leucostomum, despite overlapping distributions. Kinosternon leucostomum shows only shallow geographic divergence, whereas the K. scorpioides group is polyphyletic with up to 10 distinct taxa, some of them undescribed. We support the elevation of K. s. albogulare and K. s. cruentatum to species level. Given the deep divergence within the genus Kinosternon, we propose the recognition of three subgenera, Kinosternon, Cryptochelys and Thyrosternum, and the abandonment of the group-based classification, at least for the K. leucostomum and K. scorpioides groups. Our results show an initial split in Kinosternon that gave rise to two main radiations, one Nearctic and one mainly Neotropical. Most speciation events in Kinosternon occurred during the Quaternary and we hypothesize that they were mediated by both climatic and geological events. Additionally, our data imply that at least three South American colonizations occurred, two in the K. leucostomum group, and one in the K. scorpioides group. Additionally, we hypothesize that discordance between mitochondrial and nuclear phylogenetic signal is due to mitochondrial capture from an extinct kinosternine lineage.


Assuntos
Filogenia , Filogeografia , Tartarugas , Animais , Tartarugas/classificação , Tartarugas/genética , América do Sul , Núcleo Celular/genética , DNA Mitocondrial/genética , Análise de Sequência de DNA , Tipagem de Sequências Multilocus , Variação Genética , Teorema de Bayes
2.
Zootaxa ; 3785: 201-16, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24872178

RESUMO

We describe a new species of Anolis from the Magdalena river valley in Colombia. The new species is morphologically similar to Anolis ibanezi and A. chocorum, but differs in body and dewlap color, and head scalation. We performed an exploratory multivariate analysis based on 15 morphological characteristics of the new species and A chocorum and found that differences between both species are mainly associated with head dimensions. A phylogenetic analysis based on morphological characters suggests that the new species is nested within the "Dactyloa" clade of Anolis. Finally, we discuss phylogenetic relationships and biogeographical affinities based in its distribution. 


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Colômbia , Demografia , Feminino , Lagartos/genética , Masculino , Filogenia , Especificidade da Espécie
3.
PLoS Negl Trop Dis ; 13(3): e0007250, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30856180

RESUMO

Coral snakes of the genus Micrurus have a high diversity and wide distribution in the Americas. Despite envenomings by these animals being uncommon, accidents are often severe and may result in death. Producing an antivenom to treat these envenomings has been challenging since coral snakes are difficult to catch, produce small amounts of venom, and the antivenoms produced have shown limited cross neutralization. Here we present data of cross neutralization among monovalent antivenoms raised against M. dumerilii, M. isozonus, M. mipartitus and M. surinamensis and the development of a new polyvalent coral snake antivenom, resulting from the mix of monovalent antivenoms. Our results, show that this coral snake antivenom has high neutralizing potency and wide taxonomic coverage, constituting a possible alternative for a long sought Pan-American coral snake antivenom.


Assuntos
Antivenenos/farmacologia , Cobras Corais , Reações Cruzadas , Fatores Imunológicos/farmacologia , América , Animais , Antivenenos/isolamento & purificação , Fatores Imunológicos/isolamento & purificação , Testes de Neutralização
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