653.

Limestone White-bellied Rat

Niviventer hinpoon

French: Rat du Korat / German: Karst-Weif 3bauchratte / Spanish: Rata de vientre blanco de caliza

Other common names: Limestone Niviventer, Limestone Rat

Taxonomy. Rattus hinpoon J. T. Marshall, 1976,

“outside the entrance to the bat cave, half-way up the face of a wooded limestone cliff, 200 meters altitude,” Kaengkhoi District, Saraburi Province, Thailand.

Phylogenetic position of N. hinpoon within the genusis unclear and needs to be inves-tigated further. Monotypic.

Distribution. C Thailand.

Descriptive notes. Head-body 120- 160 mm, tail 120-160 mm, ear 17-21 mm, hindfoot 25-28 mm; weight 50-70 g. The Limestone White-bellied Rat is medium-sized and distinctive, with soft pelage. Dorsum is dull buffy gray, with spines mixed throughout. Venter is dark buffy gray, mixed with brown patches and individual hairs with gray bases and buff tips. Tail is short for the genus (¢.100% of head-body length), distinctly bicolored (dark above and white below), and covered with hair. Ears are dark brown; vibrissae are long. Feet are long and slender, with five digits,fifth reduced with small claw. Skull is slender like other species of Niviventer and indistinguishable from the Bukit White-bellied Rat ( N. bukit). There are four pairs of mammae: one pectoral, one post-axillary, one abdominal, and one inguinal. Chromosomal complement is 2n = 46, FN = 54 or 56.

Habitat. Limestone karst habitat. Limestone White-bellied Rats have been collected halfway up the face of a forested limestone cliff, outside entrance to a cave, and at base of limestone cliff in scrubby vegetation. They have also been found inside caves.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Limestone White-bellied Rat is mostly nocturnal, terrestrial, and cursorial.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Endangered on The IUCN Red List. The Limestone White-bellied Rat has a very restricted distribution and is found in Khao Yai National Park. Habitat degradation, especially in limestone forests, is a major threat. It can be locally common, but there are few details on its natural history, which are criti-cally needed to enhance its conservation.

Bibliography. Francis (2008), Latinne et al. (2011b), Li Yuchun et al. (2008), Marshall (1976, 1977b), Musser (1981a), Musser & Carleton (2005).