摘要:Palmer’s chipmunk (Neotamias palmeri) is a medium-sized chipmunk whose range is limited to the higherelevation areas of the Spring Mountain Range, Nevada. A second chipmunk species, the Panamint chipmunk (Neotamias panamintinus), is more broadly distributed and lives in lower-elevation, primarily pinyon-juniper (Pinus monophylla–Juniperus osteosperma) habitat types. Panamint chipmunks are not closely related to Palmer’s, but field identification of the 2 species is unreliable. Palmer’s chipmunk is a species of concern in the state of Nevada and is listed by the International Union for Conservation of Nature (IUCN) as endangered. As such, conservation of Palmer’s chipmunks is a priority in the Spring Mountains National Recreation Area. We sampled putative Palmer’s chipmunks from 13 sites distributed across the Spring Mountains during 2010–2011. We removed Panamint chipmunks by using DNA-based identifications and then analyzed the genetic population structure of Palmer’s chipmunks by using a panel of 9 microsatellites. Of the 228 samples that were genotyped, 186 were Palmer’s; there was no evidence of hybridization between species. Four sites had exclusively Panamint chipmunks, 5 had exclusively Palmer’s chipmunks, and 3 had a mixture of the 2 species. In this study, Palmer’s chipmunks were exclusively captured at sites above 2400 m elevation, and Panamint chipmunks were exclusively captured at sites below 2200 m. Panamint chipmunks were trapped in areas typed as pinyon-juniper, but they were also trapped at sites typed as ponderosa pine (Pinus ponderosa) and mixed conifer. Both species were trapped at 3 sites; at all 3 sites, the lower-elevation traps contained Panamint chipmunks and the higher ones Palmer’s chipmunks. Population structure within Palmer’s chipmunks was minimal: heterozygosity was relatively high, and the populations displayed no signs of recent bottlenecks. Indications are that the distribution of Palmer’s chipmunk is limited to higher-elevation areas in the Spring Mountains, but within this area, Palmer’s chipmunk occurs as a single, large, well-connected, and stable population.Neotamias palmeri es una ardilla de tamaño mediano cuyo hábitat se limita a las áreas más elevadas de Spring Mountain Range, Nevada. Una segunda especie de ardilla, Neotamias panamintinus, tiene una distribución más amplia y vive en áreas más bajas, principalmente en ambientes de pino piñonero (Pinus monophylla–Juniperus osteosperma). Si bien Neotamias panamintinus no se relaciona con Neotamias palmeri,la identificación de ambas especies en el terreno no es confiable.Neotamias palmeri es una especie en riesgo en el estado de Nevada y está incluida en la lista de especies en peligro de extinción de