Mitochondrial DNA phylogeography of Caiman crocodilus in Mesoamerica and South America.
J Exp Zool A Ecol Genet Physiol
; 309(10): 614-27, 2008 Dec 01.
Article
em En
| MEDLINE
| ID: mdl-18831056
ABSTRACT
The Neotropical crocodylian species, Caiman crocodilus, is widely distributed through Mesoamerica, northern South America, and the Amazon basin. Four subspecies are recognized within C. crocodilus, suggesting some geographic variation in morphology. In this study, we utilized mitochondrial DNA (mtDNA) sequence data from 45 individuals of C. crocodilus throughout its range to infer its evolutionary history and population structure, as well as to evaluate genealogical support for subspecies and their geographic distributions. Our molecular phylogenetic results identified five mtDNA haplotype clades with a mean sequence divergence of 3.4%, indicating considerable evolutionary independence among phylogeographic lineages. Our results were also broadly consistent with current subspecific taxonomy, with some important additional findings. First, we found substantial genetic structuring within C. c. fuscus from southern Mesoamerica. Second, though we confirmed the existence of a widespread Amazonian clade, we also discovered a cryptic and divergent mtDNA lineage that was indistinguishable from C. c. crocodilus based on external morphology. Third, we confirm the status of C. c. chiapasius as a distinct evolutionary lineage, and provide evidence that C. c. fuscus may be moving northward and hybridizing with C. c. chiapasius in northern Mesoamerica. Finally, our results parallel previous phylogeographic studies of other organisms that have demonstrated significant genetic structure over shorter geographic distances in Mesoamerica compared with Amazonia. We support conservation efforts for all five independent lineages within C. crocodilus, and highlight the subspecies C. c. chiapasius as a unit of particular conservation concern.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Filogenia
/
Variação Genética
/
DNA Mitocondrial
/
Jacarés e Crocodilos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
País/Região como assunto:
America central
/
America do sul
Idioma:
En
Revista:
J Exp Zool A Ecol Genet Physiol
Assunto da revista:
BIOLOGIA
/
FISIOLOGIA
/
GENETICA
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Panamá