284.

Short-haired Water Rat

Paraleptomys wilhelmina

French: Hydromys du Wilhelm / German: Kleine Bergmoosratte / Spanish: Rata de agua de Nueva Guinea de pelo corto

Other common names: Central Cordilleran Paraleptomys, Short-haired Hydromyine

Taxonomy. Paraleptomys wilhelmina Tate & Archbold, 1941,

“9 kilometers NE. of Lake Habbema, near Mt. Wilhelmina [Snow Mountains (Pegunungan Maoke) |, Neth-erlands New Guinea [= Province of Papua, West Papua (= Irian Jaya), New Guinea]; altitude 2800 meters.”

G. G. Musser and M. D. Carleton in 2005 listed Paraleptomys in the Hydromys division (together with Hydromys, Parahydromys, Microhydromys, and Crossomys), rather than in

the Xeromys division ( Xeromys, Leptomys, and Pseudohydromys). Molecular studies by K. C. Rowe and colleagues in 2016, however, revealed Paraleptomys as sister to Leptomys, contrary to the former assumed relationship. Further studies are required in order to determine true relationships. P. wilhelmina appears to be a species complex, the three known populations considered likely to represent three separate species. “True” P. wilhelmina are from Mount Wilhelmina (= Puncak Trikora) at 2200-2800 m; a series from lower elevations (1800-2150 m) on Wilhelmina is the second, morphologically distinct, still undescribed species; and a third population, from Tifalmin Valley (1800 m) at eastern margin of the Star (= Jayawijaya) Mountains in western Papua New Guinea, along with another unreported series, collected in the Star Mountains, represents a third, as yet undescribed species, endemic to Star Mountains of Western and Sandaun (= West Sepik) provinces of Papua New Guinea. Further study desirable. Monotypic.

Distribution. Known from three localities along the Central Range of New Guinea (Mt Trikora, Tifalmin Valley, and Star Mts), at elevations of 1800-2800 m.

Descriptive notes. Head-body 105-126 mm, tail 125-135 mm, ear 17-18-5 mm, hindfoot 27-31 mm; weight 31-35 g. This small hydromyine rat is smaller than its congener, the Northern Water Rat ( P. rufilatus). Tail is somewhat longer than head-body length; elongated hindfeet are not longer (25% of head-body length), unlike in some Leptomys . Dorsal coat is dense, soft, and woolly. Upperparts are grayish brown, slightly darker on back, and underparts are dark grayish white. Feet are white. Tail is gray above and white below, with white tip. The Short-haired Water Rat lacks the bright reddish-brown sides, head, and hindlegs and the white throat of the Northern Water Rat. Skull and mandible are similar to those of Leptomys, but Paraleptomys lacks the upper and lower third molars. Females have four mammae.

Habitat..ower and mid-montane rainforest; recorded also from an area of disturbed forest (Tifalmin Valley).

Food and Feeding. Craniodental morphology suggests an insectivorous or vermivorouslifestyle. A specimen was captured in a disturbed forest in a trap baited with sweet potato.

Breeding. No information.

Activity patterns. Short-haired Water Rats are nocturnal.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Data Deficient on The IUCN Red List. This murid appears to be abundant at the type locality. Seventy-eight specimens were captured during the 1938 Archbold Expedition. Although common in western New Guinea, this species extends no farther east than Telefomin area, being replaced east of there by Leptomys species. It is not known whether there are major threats to the Short-haired Water Rat. Populations appear to have restricted distributions. Further studies are needed in order to shed light on the taxonomy, distribution, abundance, natural history, and possible threats to these populations.

Bibliography. Aplin & Lamaris (2015), Boitani et al. (2006), Flannery & Seri (1990), Flannery (1995b), Gerrie & Kennerley (2016f), Menzies & Dennis (1979), Musser & Carleton (2005), Rowe et al. (2016b), Tate (1951), Tate & Archbold (1941).