title: Multilocus species delimitation in the Crotalus triseriatus species group (Serpentes: Viperidae: Crotalinae), with the description of two new species.
abstract: Members of the Crotalus triseriatus species group of montane rattlesnakes are widely distributed across the highlands of Mexico and southwestern USA. Although five species are currently recognized within the group, species limits remain to be tested. Genetic studies suggest that species may be paraphyletic and that at least one cryptic species may be present. We generate 3,346 base pairs of DNA sequence data from seven nuclear loci to test competing models of species delimitation in the C. triseriatus group using Bayes factor delimitation. We also examine museum specimens from the Trans-Mexican Volcanic Belt for evidence of cryptic species. We find strong support for a nine-species model and genetic and morphological evidence for recognizing two new species within the group, which we formally describe here. Our results suggest that the current taxonomy of the C. triseriatus species group does not reflect evolutionary history. We suggest several conservative taxonomic changes to the group, but future studies are needed to better clarify relationships among species and examine genetic patterns and structure within wide-ranging lineages.
authors.affiliation: Department of Biology & Burke Museum of Natural History and Culture, University of Washington, Box 351800, Seattle, WA 98195-1800, USA.; Email: brysonjr@uw.edu.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Bryson
authors.affiliation: Department of Biology & Burke Museum of Natural History and Culture, University of Washington, Box 351800, Seattle, WA 98195-1800, USA.; Email: unknown.
authors.forename: Charles W
authors.initials: CW
authors.lastname: Linkem
authors.affiliation: Department of Biology, Davidson College, Davidson, NC 28035-7118, USA.; Email: midorcas@davidson.edu.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Dorcas
authors.affiliation: Centre for Biodiversity and Conservation Biology, Royal Ontario Museum, Toronto, Ontario, Canada M5S 2C6.; Email: amyl@rom.on.ca.
authors.forename: Amy
authors.initials: A
authors.lastname: Lathrop
authors.affiliation: 16310 Avenida Florencia, Poway, California 92064, USA.; Email: jasonjones@crotalus.com.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Jones
authors.affiliation: Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Av. San Juanito Itzicuaro s/n, Col. Nueva Esperanza, C.P. 58337, Morelia, Michoacán, México.; Email: unknown.
authors.forename: Javier
authors.initials: J
authors.lastname: Alvarado-Díaz
authors.affiliation: Carretera Chapala-Jocotepec Oriente #57-1, Col. Centro, C.P. 45920, Ajijic, Jalisco, México.; Email: cgruenwald@switaki.com.
authors.forename: Christoph I
authors.initials: CI
authors.lastname: Grünwald
authors.affiliation: Centre for Biodiversity and Conservation Biology, Royal Ontario Museum, Toronto, Ontario, Canada M5S 2C6. State Key Laboratory of Genetic Resources and Evolution, and Yunnan Laboratory of Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, 32 Jiaochang Donglu, Kunming 250223, Yunnan, China.; Email: bob.murphy@utoronto.ca.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Murphy
mesh_terms: D063147:Animal Distribution; D000825:Animal Structures / Q000033:anatomy & histology / Q000254:growth & development; D000818:Animals; D049628:Body Size; D017839:Crotalus / Q000033:anatomy & histology / Q000145:classification* / Q000254:growth & development; D004272:DNA, Mitochondrial / Q000235:genetics; D017753:Ecosystem; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial