734.

Mentawai Archipelago Long-tailed Giant Rat

Leopoldamys siporanus

French: Rat de Sipora / German: Mentawai-Langschwanz-Riesenratte / Spanish: Rata gigante de cola larga de Mentawai

Other common names: Mentawai Archipelago Leopoldamys, Mentawai Long-tailed Giant Rat

Taxonomy. Mus siporanus Thomas, 1895,

Pulau Sipora, Kepulauan Mentawai, Indonesia.

Leopoldamys siporanus has been recognized as a subspeciesof L. edwards: and L. sa-banus, although it ismorphologically distinct from both. It has not been included in any phylogenetic study so its placement within the genus is unresolved, although it is probably in the L. sabanus genetic group. Monotypic.

Distribution. Siberut, Sipora, North Pagai, and South Pagai Is (Mentawai Is), off W Sumatra.

Descriptive notes. Head-body 178-287 mm, tail 220-335 mm, ear 24-28 mm, hindfoot 45-52-5 mm. No specific data are available for body weight. The Mentawai Archipelago Long-tailed Giant Rat is large, with coarse, short, and sleek pelage having spines throughout. Dorsum is dark blackish brown, with longer black guard hairs having white bases. Guard hairs are denser along spine and on rump, which makes rump much darker than rest of body, except blackish brown head. Venter is white and clearly demarcated from dorsum, with brown pectoral patches and brown mid-thoracic stripe. Ears are moderately long, rounded, and naked. Vibrissae are very long. Feet are dark brown on top, and hindfeet are long. Tail is c.119% of head-body length and blackish brown above and white or mostly white with dark brown patches below. Ears are moderately long, rounded, and naked. Vibrissae are very long. Skull is larger than that of Edwards’s Longtailed Giant Rat ( L. edwardsi) and the Indomalayan Long-tailed Giant Rat ( L. sabanus). There are four pairs of mammae: one pectoral, one post-axillary, and two inguinalpairs.

Habitat. Tropical lowland rainforest with large trees.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Mentawai Archipelago Long-tailed Giant Rat is arboreal and might be nocturnal.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. The Mentawai Archipelago Long-tailed Giant Rat is at major risk from deforestation and habitat degradation from logging and agricultural expansion (much ofits former habitat is now fruit plantations). It is estimated to occur in 13,317 km? which is probably decreasing. It is the least known species of Leopoldamys and is in need of research to understand its natural history and conservation threats.

Bibliography. Balakirev, Abramov & Rozhnov (2013), Clayton & Kennerley (2016a), Maryanto & Sinaga (2008), Musser (1981a), Musser & Carleton (2005), Musser & Newcomb (1983), Thomas (1895b).