364.

Striped Atlantic Forest Rat

Delomys dorsalis

French: Délomys sombre / German: Gestreifte Atlantische Waldratte / Spanish: Rata de bosque atléantico rayada

Other common names: Striped Delomys

Taxonomy. Hesperomys dorsalis Hensel, 1873, “Stiden Brasiliens.” Restricted by F. D. de Avila-Pires in 1994 to “Taquara, Rio Grande do Sul, Brasil.”

Delomys dorsalis is the type species of the genus. A thorough revision by P. R. Goncalves and J. A. Oliveira in 2014 recommended dismissing recognition of subspecies based on morphological grounds, ranking D. dorsalis collinus a junior synonym of D. dorsalis . Monotypic.

Distribution. Atlantic Forest of SE & S Brazil and NE Argentina, mostly along coastal mountains.

Descriptive notes. Head—body 104-135 mm, tail 100-145 mm, ear 21-22 mm, hindfoot 25-31 mm; weight 20-56 g (mean 38 g). The Striped Atlantic Forest Rat is medium-sized species of Delomys, with soft and dense dorsal pelage, predominantly dark cinnamon-brown and without bright yellow lateral line or patch;tail as long as head-body length. Vibrissae are long, extending to or beyond tips of pinnae when laid back along head. There are 6-8 mammae. Chromosomal complement is 2n = 82, FN = 80.

Habitat. Submontane and montane forests frequently associated with Araucaria angustifolia (Araucariaceae) from sea level to elevations above 2000 m.

Food and Feeding. The Striped Atlantic Forest Rat eats fruits, seeds, invertebrates, and fungi.

Breeding. Striped Atlantic Forest Rats are reproductively active year-round, although breeding activity is reduced in winter. Postpartum estrus occurs, gestation lasts 21-22 days, and litters have 2-5 young.

Activity patterns. The Striped Atlantic Forest Rat is nocturnal. It is reported to be primarily terrestrial, although individuals have remarkable scansorial abilities and can seasonally occur in subcanopy vegetation.

Movements, Home range and Social organization. Striped Atlantic Forest Rats move among and shelter in clutters of logs, organic debris, mossy roots, tangled bamboo, and herbaceous understory rather than frequenting open areas on forest floor. Apparently, Striped Atlantic Forest Rats experience peaks of abundance related to availability of seeds of Araucaria angustifolia in mixed forests with conifers.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Striped Atlantic Forest Rat has a wide distribution and presumably large overall population.

Bibliography. de Avila-Pires (1994), Bonvicino & Geise (1995), Cademartori (2002), Cademartori et al. (2004, 2005), Dalmagro & Vieira (2005), Goncalves & Oliveira (2014), Hershkovitz (1998), Massoia (1962), Thomas (1917b), Vieira et al. (2006), Voss (1993, 2015a).