712.

Cordoba Vesper Mouse

Calomys venustus

French: Calomys du Cordoba / German: Cordoba-Vespermaus / Spanish: Raton laucha de Cordoba

Other common names: Cordoba Laucha

Taxonomy. Oryzomys (?) venustus Thomas, 1894, Cosquin, Cordoba, Argentina.

This species is monotypic.

Distribution. C Argentina (Santiago del Estero, Cordoba, and San Luis provinces).

Descriptive notes. Head-body 64-163 mm, tail 40-110 mm, ear 10-7-23 mm, hindfoot 18-29 mm; weight 21-51 g. The Cordoba Vesper Mouse is the largest species of Calomys (greatest length of skull ¢.28-7 mm). Dorsal pelageis soft and long, with dull brownish or yellowish gray hairs with black-lined tips; sides are sandy buff. Indistinct buffy line separates sides and venter; underparts are pale gray, with individual hairs gray at bases and white at tips. In many specimens, hairs of chin are white to their bases. Ears are medium to large and almost always with buffy tuft at bases and buffy post-auricular spot, although it may not be as obvious as in other species. Hands and feet are well-haired and white. Tail is shorter than head-body length, well-haired, and distinctly bicolored (brown above and white on sides and below). There are 5-7 pairs of mammae.

Habitat. Areas with relatively high vegetative cover including crop field edges, roadsides, railway banks, and remnant areas of native vegetation

Food and Feeding. The Cordoba Vesper Mouse is omnivorous, with a tendency toward folivory in spring and autumn and granivory in summer.

Breeding. Reproduction of the Cordoba Vesper Mouse follows a cyclical seasonal pattern characterized by period of repose in August-September and variable period of sexual activity in May-June; three pregnancy peaks were observed (spring, summer, and late summer), each with a different average litter size. The Cordoba Vesper Mouse is sexually dimorphic, and a promiscuous-polygynous mating system was suggested for it.

Activity patterns. The Cordoba Vesper Mouse is terrestrial and crepuscular. Facultative torpor has been noted.

Movements, Home range and Social organization. Densities fluctuate seasonally, with peak in May-June, and multiannually in response to previous year’s spring and summer rainfall and spring mean temperature.

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

Bibliography. Andreo et al. (2009), Bozinovic & Rosenmann (1988a), Castellarini & Polop (2002), Castellarini, Agnelli & Polop (1998), Castellarini, Provensal & Polop (2002), Caviedes-Vidal et al. (1990), Chiappero et al. (2016), Cordeiro-Estrela et al. (2008), D'Elia & Jayat (2016), Gomez, Provensal & Polop (2007), Gomez, Sommaro et al. (2011), Kravetz & Polop (1983), Martinez et al. (2016), Niebylski et al. (1993), Polop (1996), Polop & Provensal (1999, 2000), Polop & Sabattini (1993), Polop et al. (2005), Priotto & Polop (1997 2003), Priotto, Steinmann & Polop (2002), Priotto, Steinmann, Provensal & Polop (2004), Provensal (2001), Provensal & Polop (2008), Salazar-Bravo (2015¢), Steinmann et al. (1997), Vitullo et al. (1990), Yunes et al. (1991).