717.

Lowland Gerbil Mouse

Eligmodontia typus

French: Eligmodonte de Cuvier / German: Eigentliche Hochlandwiistenmaus / Spanish: Raton colilargo de tierras bajas

Other common names: Eastern Patagonian Laucha, Highland Gerbil Mouse

Taxonomy. Eligmodontia typus F. Cuvier, 1837, “environs de Buenos-Ayres [= Buenos Aires],” Argentina .

Provenance of type material has been discussed and was probably collected in south-western Buenos Aires Province, Argentina, but this issue and taxonomy of E. typus need further research attention. Monotypic.

Distribution. WC to S Argentina .

Descriptive notes. Head-body 85 mm, tail 96 mm, ear 18 mm, hindfoot 23-5 mm; weight 17 g (mean values derived from males and females from north-eastern Patagonia). See general characters of the genus under the Hairy-footed Gerbil Mouse ( E. hirtipes) account. The Lowland Gerbil Mouse is a small species of Eligmodontia, with tail slightly larger than head-body length. Hair is short, with overall brownish dorsal tones. Back is separated from venter by buffy lateral line of varying distinctiveness; underparts are white, with hairs gray or white at their bases throughout or confined mainly to margins. Ears are moderately long (20-23% of head-body length). Forefeet and hindfeet are white above; soles have short white hair. Tail is 110-121% of headbody length, slightly bicolored with dark and especially wide dorsal stripe; it usually either lacks terminal pencil or has one less than 5 mm long.

Habitat. Mostly sandy areas covered by creosote bush ( Larrea, Zygophyllaceae) or mesquite ( Prosopis, Fabaceae), open shrublands, and areas disturbed by cattle grazing primarily at elevations below 1000 m.

Food and Feeding. The Lowland Gerbil Mouse mainly eats seeds, followed by leaves and arthropods; seed hoarding has been reported. It resists water deprivation and concentrates urine as a strategy to minimize water loss.

Breeding. In north-eastern Patagonia, Lowland Gerbil Mice with reproductive signals are recorded in November—March; number of embryos 2-6.

Activity patterns. The Lowland Gerbil Mouse is nocturnal, terrestrial, and a skilful climber.

Movements, Home range and Social organization. Locomotion of the Lowland Gerbil Mouse varies according to openness of habitat. Mean travel distance was 76-8 m, and mean area traveled was 581-9 m? distances traveled beneath shrubs were longer (1-3 m) than distances beneath subshrubs (0-65 m), and distances traveled beneath both were longer than between open microhabitats (0-35 m). In Mendoza, averaged home range was 812-9 m* without significant differences between males and females.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Bozinovic, Cruz-Neto et al. (2007), Campos et al. (2007), Cassola (2016x), Corbalan (2006), Cor balan & Debandi (2006), Corbalan & Ojeda (2004), Corbalan et al. (2006), Cuvier (1837), Da Silva (2011), Diaz & Ojeda (1999), Giannoni, Borghi et al. (2005), Giannoni, Campos et al. (2013), Giannoni, Dacar et al. (2001), Hershkovitz (1962), Lanzone, Braun et al. (2015), Lanzone, Ojeda & Gallardo (2007), Lessa et al. (2010), Mares (1975b, 1988), Mares et al. (2008), Massoia & Fornes (1964b), Sikes et al. (1997), Taraborelli, Borruel & Mangeaud (2009), Taraborelli, Dacar & Giannoni (2003), Tiranti (1997), Udrizar (2009).