title: Biogeography of "Cyprinella lutrensis": intensive genetic sampling from the Pecos River 'melting pot' reveals a dynamic history and phylogenetic complexity.
abstract: Thorough sampling is necessary to delineate lineage diversity for polytypic "species" such asCyprinella lutrensis. We conducted extensive mtDNA sampling (cytochrome b and ND4) from the Pecos River, Rio Grande, and South Canadian River, New Mexico. Our study emphasized the Pecos River due to its complex geological history and potential to harbor multiple lineages. We used geometric-morphometric, morphometric, and meristic analyses to test for phenotypic divergence and combined nucDNA with mtDNA to test for cytonuclear disequilibrium and combined our sequences with published data to conduct a phylogenetic re-assessment of the entireC. lutrensisclade. We detected five co-occurring mtDNA lineages in the Pecos River, but no evidence for cytonuclear disequilibrium or phenotypic divergence. Recognized species were interspersed amongst divergent lineages of "C. lutrensis". Allopatric divergence among drainages isolated in the Late Miocene and Pliocene apparently produced several recognized species and major divisions within "C. lutrensis". Pleistocene re-expansion and subsequent re-fragmentation of a centralized lineage founded younger, divergent lineages throughout the Rio Grande basin and Edwards Plateau. There is also evidence of recent introductions to the Rio Grande, Pecos and South Canadian Rivers. Nonetheless, deeply divergent lineages have coexisted since the Pleistocene.
authors: Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico 87131.
authors: Megan J
authors: MJ
authors: Osborne
authors: Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico 87131.
authors: Tracy A
authors: TA
authors: Diver
authors: Department of Zoology, Weber State University, 1415 Edvalson Street, Dept. 2505, Ogden, Utah 84408-2505.
authors: Christopher W
authors: CW
authors: Hoagstrom
authors: Department of Biology and Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico 87131.
authors: Thomas F
authors: TF
authors: Turner
keywords: allopatric speciation; cryptic diversity; lineage persistence; phylogenetic sampling; polytypic taxa; species introductions; widespread species