42.

Lined Pocket Mouse

Chaetodipus lineatus

French: Souris-a-abajoues rayée / German: Streifen-Rauhaartaschenmaus / Spanish: Raton de abazones de lineas

Taxonomy. Perognathus lineatus Dalquest, 1951,

1 km south of Arriaga, San Luis Potosi, Mexico.

Populations of pocket mice within the south-eastern distribution of C. nelsoni in central San Luis Potosi and extreme northeastern Zacatecas have been described as a separate species C. lineatus that is supposedly sympatric throughout its distribution with C. nelsoni, including several specific locations. Nowhere else in the entire distribution of the genus are two species of smooth-haired or coarse-haired pocket mice of the modern lineage of this genus widely sympatric. Specimens trapped at supposed sites of sympatry (Matehuala, Arriaga, and Penon Blanco) have yielded only specimens with chromosomal complement and mitochondrial sequences of C. nelsoni, and it is considered most likely that C. lineatus is not a valid species, but instead is based on individuals of C. nelsoni with a pelage that resembles a juvenile pelage. The speciesis retained here pending evidence confirming or rejecting its speciesstatus (e.g. molecular sequencing of type specimens). Monotypic.

Distribution. NC Mexico (SE Zacatecas and SW San Luis Potosi).

Descriptive notes. Head-body mean 74 mm, tail mean 92 mm, ear mean 7 mm, hindfoot mean 22 mm; weight 17 g. There is no significant secondary sexual dimorphism. The Lined Pocket Mouse is coarse-haired and medium-sized for the genus, with tail that is longer than head-body length, sparsely haired on basal one-half; terminal one-half is crested, penicillate, and indistinctly bicolored. Pelage is relatively coarse but lacking spines on rump. Pelage is brownish gray or dull gray, with faint and indistinct buffy lateral line, and white under parts. Chromosomal complement has not been described.

Habitat. Along rocky banks and cliffs and along old stone walls in desert plains, at elevations of 1600-2400 m. Small burrows of Lined Pocket Mice are dug at bases of desert shrubs, particularly thorny bushes.

Food and Feeding. Diet of the Lined Pocket Mouse consists largely of seeds of shrubs, annuals, and grasses, butit also includes smaller amounts of green vegetation and insects. It feeds on seeds of prickly pear cactus (Opuntia, Cactaceae) but apparently not red pulp ofthe fruit. Food items are collected in external, fur-lined cheek pouches and transported back to burrows, where they are stored in burrow caches. The Lined Pocket Mouse does not need to drink water, subsisting entirely on water from its food and water produced as a byproduct of metabolism.

Breeding. There is no information available for this species.

Activity patterns. The Lined Pocket Mouse is nocturnal and terrestrial, and it is active throughout the year. It rarely strays from shelter of bushes or rocks while foraging.

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. Classified as Data Deficient on The IUCN Red List.

Bibliography. Aquino & Neiswenter (2014), Best (1993a, 1993c), Castro-Arellano & Vazquez (2008a), Ceballos & Oliva (2005), Patton (2013), Williams et al. (1993).