PARENT SESSION

Systematics/Zoogeography 1 -- Session Chair: Link Olson-- Nelson Hall East, Goodwin Forum

PHYLOGEOGRAPHY OF THE DESERT POCKET MOUSE (CHAETODIPUS PENICILLATUS) WITH EMPHASIS ON THE CONSERVATION OF C. P. SOBRINUS. Zane L. Marshall, Brett R. Riddle and Jef Jaeger. Department of Biological Sciences, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Las Vegas, NV, USA.

ABSTRACT- The desert pocket mouse (Chaetodipus penicillatus) includes five described continental subspecies that occupy low elevation desertscrub habitats across the Mojave and Sonoran deserts. Chaetodipus p. sobrinus is the most northerly distributed subspecies, where it occurs in relatively disjunct populations that are restricted to fluvial sands along the margins of riparian corridors in northwestern Arizona, extreme southwestern Utah, and southern Nevada. Because of significant anthropogenic disturbance and the introduction of nonnative vegetation (e.g. Tamarix spp.), the viability of C. p. sobrinus is in question. We employ phylogenetic analyses of a directly sequenced 450bp region along the hyper variable 5′ end of the mitochondrial DNA Control Region to build on previous molecular studies and further elucidate phylogeographic relationships within and among the five subspecies. Results of this research include the identification of two major clades comprising the recognized subspecies with much geographic intermixing of haplotypes of C. p. angustirostris, C. p. pricei, and C. p. penincillatus in more southern regions. Chaetodipus p. stephensi, from Death Valley, and C. p. sobrinus form a distinct lineage nested within one of these major clades that is geographically distinct and restricted to more northern portions of the eastern Mojave Desert. This group appears to be more broadly distributed in this northern region than previously thought. Additional findings of this research include a more thorough understanding of the contemporary distribution and population status of C. p. sobrinus. With these results, we test the current taxonomy of C. p. sobrinus, identify conservation units for this taxon, and provide recommendations regarding its conservation.

KEY WORDS: conservation, Chaetodipus, phylogeograhy