endemic to a single state or province

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (<100-250 square km (less than about 40-100 square miles)) Known only from 4 canyons in the Tehachapi Mountains, northeastern Kern County, California. Elevational range 4000-5300 ft. Probably ranges along entire east slope of Tehachapi/Sierra Nevada between about Walker Pass and Bishop.

Length: 17 cm

Comments: Desert shrub and Joshua tree communities with scattered pinyon pines. Occupies underground burrow when inactive. Young are born in underground burrows.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Comments: Probably similar to other members of this genus which feed primarily on seeds and store food in underground storage chambers.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 6 - 20

Comments: Probably occurs in other canyons in range, but much of potential range is not easily accessible.

2500 - 10,000 individuals

Comments: A guess. Probably seasonally abundant periodically within limited range.

United States

Rounded National Status Rank: N2 - Imperiled

Rounded Global Status Rank: T2 - Imperiled

Reasons: Small range in southern California; apparently common in appropriate habitat; no known threats; post-glacial climatic changes might be a threat, but data are lacking; no protected occurrences.

Degree of Threat: C : Not very threatened throughout its range, communities often provide natural resources that when exploited alter the composition and structure over the short-term, or communities are self-protecting because they are unsuitable for other uses

Comments: Habitat relatively self-protecting.

Management Requirements: Avoid excessive livestock grazing.

Biological Research Needs: Obtain data on all aspects of life history and demography; investigate taxonomic relationships within the PARVUS group of Perognathus.

Global Protection: None. No occurrences appropriately protected and managed

Comments: Known localities are on federal land, but no special protection is provided.

Needs: Protect from development and excessive grazing all canyons with an EO.

Comments: PEROGNATHUS XANTHONOTUS is here regarded as a subspecies of P. PARVUS. Williams et al. (1993) and Jones et al. (1997) concluded that P. XANTHONOTUS does not warrant recognition as a distinct species. Patton (in Wilson and Reeder 1993) stated that P. XANTHONOTUS probably should be regarded as a subspecies of P. PARVUS.

See Best (1994) for a key to the species of Perognathus. See Ryan (1989) for a phylogenetic analysis of Heteromyidae based on myology.