Euneomys mordax Thomas 1912

671.

Biting Chinchilla Rat

Euneomys mordax

French: Eunéomys du Mendoza / German: BeiR-Chinchillamaus / Spanish: Rata chinchilla mordaz

Other common names: Biting Chincilla Mouse, Large Euneomys

Taxonomy. Euneomys mordax Thomas, 1912, “Fort San Rafael, Province of Mendoza,” Argentina. According to O. P. Pearson and M. I. Christie in 1991, accuracy of the type locality is in doubt. Questioned by O. P. Pearson and H. A. Lagiglia in 1992 and changed to probably near Peteroa Volcano, on the Argentinean—Chilean border.

This species is monotypic.

Distribution. WC Argentina (Mendoza and Neuquén provinces) and adjacent region of Chile.

Descriptive notes. Head-body 145-149 mm, tail 78-85 mm, ear 24-27 mm, hindfoot 28-32 mm; weight 78-86 g. The Biting Chinchilla Ratis larger than that the Patagonian Chinchilla Rat (E. chinchilloides) and Peterson’s Chinchilla Rat (E. peterson). Its fur is long, thick, and woolly; hairs on back are c.12-13 mm long; general color is dull gray, belly paler, not sharply defined, and hairs broadly washed with cream buff; ears are of medium length, well-haired, and blackish; manus and pes are dull grayish white above; foreclaws are not enlarged; and tail is thickly haired, grayish white with indistinct darker line above. Incisors very broad and heavy, with strong groove in more or less central position. Chromosomal complement is 2n = 42, FN = 66.

Habitat. Typically wet alpine meadows characterized by deep moist soils and nearly 100% ground coverof grasses, sedges, brush, and patches of southern beech (Nothofagus antarctica, Nothofagaceae) at elevations of 1600-3300 m (mostly above 1800 m). The Biting Chinchilla Rat appears to be relatively ecologically specialized.

Food and Feeding. The Biting Chinchilla Rat is herbivorous.

Breeding. The Biting Chinchilla Rat apparently breeds in summer (December—March).

Activity patterns. The Biting Chinchilla Ratis terrestrial.

Movements, Home range and Social organization. Biting Chinchilla Rats were collected in clearly defined systems of runways and tunnels.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Nevertheless, recent extirpations suggest that the Biting Chinchilla Rat could be threatened by climatic change, particularly considering its restricted distribution in high-elevation Andean habitats.

Bibliography. Braun & Pardinas (2015), D'Elia (2016a), Greer (1965), Jayat et al. (2006), Mann (1944), Ojeda, D’Elia et al. (2005), Ojeda, Novillo et al. (2015), Pearson & Christie (1991), Pearson & Lagiglia (1992), Pine et al. (1979), Reise & Gallardo (1990), Reise & Venegas (1987), Hershkovitz (1962), Tammone et al. (2016), Thomas (1912c¢).