173.

Russet Hairy-tailed Rat

Batomys russatus

French: Batomys roux / German: Dinagat-Haarschwanzratte / Spanish: Rata de cola peluda rojiza

Other common names: Dinagat Hairy-tailed Rat, Russet Batomys

Taxonomy. Batomys russatus Musser, Heaney & Tabaranza, 1998,

Libjo (= Albor), Plaridel Municipality, Surigao del Norte Province, Dinagat Island, Philippines.

Described on morphological grounds; no genetic data available for this species. Monotypic.

Distribution. Endemic to Dinagat I, Philippines.

Descriptive notes. Head-body 140-151 mm, tail 102-118 mm, ear 16-18 mm, hindfoot 30-31 mm; weight 115 g. The Russet Hairy-tailed Ratis the smallest and most colorful species of Batomys, with short, sleek fur. Dorsal pelage is a glossy reddish brown with slender guard hairs that barely extend past the overfur and have an unpigmented tip. Ventral pelage is bright ocherous slightly infused with the pale gray gases of the hairs. Cheeks have an ocherous tone and ventral pelage is not sharply demarcated from dorsal pelage, blending along the sides. Some specimens have white patches on the throat or pectoral and inguinal regions or an entirely white chest region. Ears are small and dark gray with scantily distributed short russet hairs and vibrissae are shorter than in the Hamiguitan Hairy-tailed Rat ( B. hamiguitan). Tail is moderately hairy, uniformly brown, and ends with a tiny thin tuft; it is shorter (c.73-80%) than head-body length. Feet are all unpigmented white, hindfeet being moderatelylong and wide with brownish russet marking on the dorsal metatarsal surface and unpigmented digits and claws. Hypothenar pads are large relative to the size of the thaner, which is smaller in other species. Females have two pairs of mammae, both inguinal. Skullproportions are smaller than in the Luzon Cordillera Hairy-tailed Rat ( B. grantii) and the Mindanao Hairy-tailed Rat ( B. salomonseni), with an elongated posterior cingulum and the back of each first and second lower molar.

Habitat. Lowland tropical forest at around 350 m.

Food and Feeding. Little is known, but specimens were caught in traps bated with fried coconut coated with peanut butter.

Breeding. No information.

Activity patterns. The Russet Hairy-tailed Rat is probably terrestrial, and it has been captured on the ground.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Endangered on The IUCN Red List because it has a small distribution, within which there is important degradation ofits habitat due to mining, logging, and agriculture; hunting is also a threat. It probably occurs at very low abundances, and only three specimens are known, dating from 1972 and 1995.

Bibliography. Balete et al. (2008), Musser, Heaney & Tabaranza (1998).