104. Mexican Least Shrew Cryptotis soricinus French: Musaraigne soricine / German: Mexiko-Kleinohrspitzmaus / Spanish: Musarana minima de México Taxonomy. Blarina soricina Merriam, 1895, “ Tlalpam [= Tlalpan], Valley of Mexico (altitude, 7,600 feet [= 2317 m]),” Mexico. Restricted by L. N. Carraway in 2007 to “latitude 19-26°N, longitude 99-15°W.” Cryptotis soricinus traditionally has been considered a subspecies of C. parvus but is now recognized as a distinct species in the C. parvus group, somewhat tentatively, based primarily on limited morphological data. Monotypic. Distribution. Distrito Federal and México (C Mexico). Descriptive notes. Head-body ¢.65-69 mm, tail 23-5 mm (holotype), hindfoot 12-12:5 mm. No specific data are available for body weight. The Mexican Least Shrew is small, similar to the North American Least Shrew (C. parvus). Dorsum is very dark brown, and venter is lighter brown. Forefeet are relatively broad, with short broad claws; feet are small and dusky in color. Tail is short (¢.34% of head-body length), covered with short hair, and brown above and slightly lighter below. Eyes are diminutive, and ears are small and barely visible under fur. The Mexican Least Shrew is distinguished from Berlandier’s Least Shrew (C. berlandieri) by its light brown venter and from the Puebla Least Shrew (C. pueblensis) by breadth across M* and M* (3-8—4-1 mm). Skull is typical of other least shrews. Teeth are reddish, and there are four unicuspids. Habitat. Primarily livestock pastures with dense herbaceous cover and sometimes pine and pine-oak forests at elevations of 1250-2350 m. Food and Feeding. No information. Breeding. No information. Activity patterns. No information. Movements, Home range and Social organization. There is no specific information for this species, but the Mexican Least Shrew might be ecologically similar to the North American Least Shrew. Status and Conservation. Not assessed on The IUCN Red List. The Mexican Least Shrew has a very restricted distribution (32,000 km?®) but does not seem to have any major threats; it is common in livestock pastures, implying it can withstand some habitat degradation. Additional research on ecology, threats, and taxonomy are needed. Bibliography. Carraway (2007), Castro-Arellano (2014a), Choate (1970).

Published as part of Russell A. Mittermeier & Don E. Wilson, 2018, Soricidae, pp. 332-551 in Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona :Lynx Edicions on page 433, DOI: 10.5281/zenodo.6870843