Mallomys aroaensis

251.

De Vis’s Woolly Rat

Mallomys aroaensis

French: Mallomys de De Vis / German: De-Vis-Riesenbaumratte / Spanish: Rata lanuda de De Vis

Other common names: De Vis's Mallomys

Taxonomy. Dendrosminthus aroaensis De Vis, 1907,

“head of Aroa River, in British New Guinea [= Central Province, Papua New Guneal].”

Mallomys forms a clade with Abeomelomys and Mammelomys. There are at least two undescribed species, one from Mount Bosavi (the Bosavi Woolly Rat) and the other from the Arfak Mountains (the Arfak Woolly Rat), and another possibly new species from the Foja Mountains (the Foja Woolly Rat) that is known only from photographs. The subspecies hercules is distinctive, and future studies will probably find that it merits treatment as a separate species. Two subspecies recognized.

Subspecies and Distribution.

M.a.aroaensisDeVis,1907—ECentralCordilleraofNewGuinea.

M. a. hercules Thomas, 1912 — Huon Peninsula, NE New Guinea.

Descriptive notes. Head-body 344-415 mm, tail 335-435 mm, ear 25-3-27-5 mm, hindfoot 64-4-72 mm; weight 1.4-2 kg. De Vis’s Woolly Rat is an extremely large species of giant rat. Pelage is long, dense, and somewhat woolly, with long dark guard hairs throughout. Dorsal pelage is a dark blackish with more speckling owing to banding on hairs (in aroaensis) to grayish black with less speckling (hercules), also with distinct dorsal stripe. Ventral pelage is white, being a thinner area in subspecies hercules. Feet are blackish. Ears are flesh-colored; vibrissae are long. Tail is long (¢.95-105% of head-body length), black basally and unpigmented white for distal half. Skull has a relatively broader rostrum and more inflated frontal region. Incisors have orange enamel, rather than white as in the Alpine Woolly Rat (M. gunung). There are three pairs of mammae, with one pectoral and two inguinal pairs.

Habitat. Tropical moist forest, degraded forest, areas of regrowth, and old rural gardens, at elevations of 1100-2700 m.

Food and Feeding. De Vis’s Woolly Rat is herbivorous, probably feeding on leaves and shoots.

Breeding. Litter size consists of a single young, which is probably dependent on its mother for a prolonged period. A lactating female with young (male weighing 880 g) was caught in a burrow in January; a female with an advanced embryo was captured.

Activity patterns. De Vis’s Woolly Rat is nocturnal. It is terrestrial and arboreal, and builds nests in dens and burrows, sometimes among rocks, and feeding in trees.

Movements, Home range and Social organization. One burrow had two animals in it, a male and a female.

Status and Conservation. Classified as Least Concern on The IUCN Red List. De Vis’s Woolly Rat has a wide distribution and there are no major threats to it, although it is hunted for food throughout its range. Further research is needed in order fully to understand this species’ natural history, evolution, and threats.

Bibliography. Flannery (1995b), Flannery et al. (1989), Helgen, Bonaccorso et al. (2016), Musser & Carleton (2005), Steppan & Schenk (2017).