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Chaetodipus nelsoni occurs on rocky substrates across the Mexican Altiplano. We investigated phylogeographic diversity within the species using morphologic, karyotypic, and molecular data. Data from nuclear (AFLP) and mitochondrial DNA support three distinct genetic groups with minimal substructuring coincident with biogeographic barriers previously identified in the Chihuahuan Desert and drainage basins of the Altiplano. We examined the morphological and karyotypic data in light of the molecular data. The results support recognition of three species within the currently accepted widespread C. nelsoni: 1) C. nelsoni restricted to a distribution centered on the El Salado River Basin; 2) elevation of C. n. collis to species, with two subspecies: one centered on Trans-Pecos Texas, the other on the Mapimí Basin (new subspecies); and 3) recognition of a new species, C. durangae, centered on the Nazas Basin and upper Río Mezquital drainage.
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Phylogeography, systematics, and conservation status of pocket mice ( Chaetodipus ) of the Sonoran–Sinaloan thorn forest
Abstract Three species of pocket mice (Chaetodipus artus, C. goldmani, and C. pernix) characterize the Sinaloan subregion of the Sonoran regional desert. They occur primarily in Sinaloan thornscrub and monsoon (dry deciduous) forest biotic communities, both of which have suffered from agricultural conversion. Sinaloan thornscrub occurs along the coastal plains of southern Sonora and Sinaloa, México, and grades into monsoon forest in the foothills of the Sierra Madre Occidental. We describe the geographical and ecological distributions of the 3 species of Chaetodipus, evaluate evolutionary relationships within each species based on mitochondrial DNA sequence data, and compare these to previously described phenetic, allozymic, and chromosomal variation. We elevate the subspecies of C. pernix to full species, delineate evolutionary units within C. goldmani and C. artus that we formally recognize as subspecies, and evaluate the conservation status of all 3 species of Chaetodipus.
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- Award ID(s):
- 1757316
- PAR ID:
- 10498757
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Mammalogy
- Volume:
- 105
- Issue:
- 3
- ISSN:
- 0022-2372
- Format(s):
- Medium: X Size: p. 543-562
- Size(s):
- p. 543-562
- Sponsoring Org:
- National Science Foundation
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