25 research outputs found
PHYLOGENETIC RELATIONSHIPS AMONG WEST INDIAN XENODONTINE SNAKES (SERPENTES; COLUBRIDAE) WITH COMMENTS ON THE PHYLOGENY OF SOME MAINLAND XENODONTINES
The evolutionary relationships of the West Indian (W. I.) xenodontine snake assemblage has been considered as either monophyletic or paraphyletic. Allozyme data from protein electrophoresis were used to estimate the phylogeny of the W. I. xenodontine snakes. Forty-two species from 25 genera (mainland and W. I. taxa) were examined. The phylogenetic relationships were estimated using parsimony analyses with successive approximation weighting on the data coded two ways: (1) the allele as the character and (2) the locus as the character. The most parsimonious trees from both coding methods indicated a non-monophyletic W. I. xenodontine assemblage. Three W.I. groups were recovered in both coding methods: (1) Jamaican Arrhyton and Darlingtonia, (2) Uromacer and the Cuban Arrhyton, and (3) Alsophis, Ialtris, and the South American Alsophis elegans. The relationships of Hypsirhynchus, Antillophis and Arrhyton exiguum were unstable. Nomenclatural changes are recommended for Darlingtonia, Arrhyton, Ialtris and Alsophis
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Cricosaura, C. typica
Number of Pages: 3Integrative BiologyGeological Science
PHYLOGENY OF SOME MIDDLE AMERICAN PITVIPERS BASED ON A CLADISTIC ANALYSIS OF MITOCHONDRIAL 12S AND 16S DNA SEQUENCE INFORMATION
The cladistic relationships of several Middle American pitvipers representing the genera Bothrops (sensu stricto), Bothriechis, Cerrophidion, Lachesis and Porthidium were determined using mitochondrial 12S and 16S DNA sequence information. Maximum parsimony analyses were performed using PAUP on aligned sequences that included published information for related taxa. Two sets of analyses were conducted: one disregarding gaps in the aligned matrix, and another with gaps treated as a fifth base. When gaps were excluded resolution declined, although the general arrangement of the taxa changed little. A consistent relationship was the grouping of ((Porthidium, Bothriechis) Lachesis). The placement of Lachesis, as nested within other bothropoid genera, is only partially supported by results of other authors. The arrangement of Crotalus, Bothrops and Cerrophidion was ambiguous when gaps were discounted. In both trees, Agkistrodon was basal to the New World forms. The remaining genera, Trimeresurus (Protobothrops), Vipera, Azemiops, and Coluber, were uniformly distant to the former taxa. Also of interest is the lack of close relationship, based on the DNA data here and elsewhere, between Bothrops and Porthidium. This is in striking contrast to results based on morphologic and allozymic analyses of previous studies. It is concluded that additional DNA sequence information from a larger sample of taxa will be necessary to better assess the phylogenetic relationships among Middle American and related pitvipers
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Cnemidophorus hyperythrus
Number of Pages: 6Integrative BiologyGeological Science
Cryptic Diversity and Conservation of Gopher Frogs across the Southeastern United States
Identifying cryptic biodiversity is fundamental to evolutionary biology and to conservation efforts. This study investigated range-wide genetic diversity of Gopher Frogs, Lithobates capito, across the southeastern United States coastal plain to determine implications for taxonomy and conservation. We collected data for two mtDNA regions in 21 populations to identify genetic structure across the geographic distribution of the species. Based on population genetic, phylogenetic, and genealogical analyses, we recovered three reciprocally monophyletic mtDNA lineages corresponding to mainland coastal plain populations and two lineages within peninsular Florida. Breakpoints for these lineages did not occur in previously identified hotspots of amphibian phylogeographic breaks and did not follow currently recognized subspecies designations. We recommend these lineages be recognized as separate distinct population segments and be considered separately by the U.S. Fish and Wildlife Service for listing under the Endangered Species Act. Additionally, we propose an evolutionary hotspot for amphibians that deserves further attentio
Best practices: in the 21st century, taxonomic decisions in herpetology are acceptable only when supported by a body of evidence and published via peer-review
This paper was written by nine authors from five continents, and supported by a further 80 academics and many major herpetological societies including the World Congress of Herpetology, in reaction to burgeoning number of species descriptions being published in herpetology by a small number of individuals through their own self-published "journals" which lack any peer-review