297.

Champion’s Tree Mouse

Pogonomys championi

French: Pogonomys de Champion / German: Champion-Greifschwanzratte / Spanish: Raton arboricola de Champion

Other common names: Champion's Pogonomys

Taxonomy. Pogonomys championi Flannery, 1988,

Ofektaman, 1400 m, Telefomin Valley, Sandaun Provomce, Papua New Guinea.

Although more studies of the relationships within Hydromyini are needed, Pogonomys wasfoundin S.J. Steppan andJ. J. Schenk’s 2017 analysis to form a genetic clade with Hyomys (to which it is sister taxon), Chiruromys, Macruromys, Lorentzimys, and Anisomys, although with relatively low support.

P. championi is closely related to P. sylvestris, with which it may be conspecific. Monotypic.

Distribution. Telefomin and Tifalmin valleys in the upper Sepik River drainage, NC New Guinea.

Descriptive notes. Head-body 112-136 mm, tail 149-170 mm, ear 11-14 mm, hindfoot 20-24 mm; weight 40-66 g. Champion’s Tree Mouse is a small species of Pogonomys with pelage long, soft, and fine. Dorsal pelage is sepia, being redder along sides, more so than in the Chestnut Tree Mouse (FP. macrourus), with long black guard hairs and straw-colored underfur; closer inspection reveals that it also has a peppered appearance and a dark and thin eye-ring. Ventral pelage is grayish white with gray-based fur, although under the chin it is pure white, while some specimens have a small pure white patch on chest. Feet are short, broad, and covered sparsely in white hairs. Ears are of similar color to dorsal pelage; vibrissae are long and black. Tail is long (¢.130% of head-body length), slender, dorsally prehensile at tip, and uniformly dark, becoming lighter with age until it isan ivory color, which is unique for the genus. Skull has a short and bowed incisive foramen and a narrow rostrum. There are three pairs of mammae, one pectoral and two inguinal. Various species of nematode have been recorded from this species.

Habitat. Tropical moist forest as well as rural gardens, being tolerant of disturbed habitat. Champion’s Tree Mouse occurs at elevations of 1400-2300 m. It may be sympatric with the Gray-bellied Tree Mouse ( P. sylvestris) at ¢.1400 m.

Food and Feeding. Champion’s Tree Mouse is probably herbivorous.

Breeding. Little is known, but two suckling young were found in February.

Activity patterns. Champion’s Tree Mouse is nocturnal, spending the night foraging in trees and bushes and the day in a burrow. Although mostly arboreal, it nests in burrows. Burrow entrances are 60 mm wide, and the tunnel is 2 m long, ending with a nest chamber with dry vegetation; above the nest chamberis a tunnel with an escape hatch, terminating in a hole 20-30 mm in diameter.

Movements, Home range and Social organization. Multiple individuals can live in a single burrow. One burrow contained five males and one female, another had a female and two suckling young, and a third had four males and three females, two of which were subadults.

Status and Conservation. Classified as Data Deficient on The IUCN Red List. Champion’s Tree Mouse has a highly restricted distribution, although it isgenerally common within its small range. It may be threatened by local hunting with dogs for food and by general disturbance, although it can tolerate disturbed habitats. Further research is needed in orderfully to understand this species’ natural history and evolution, and threatsto it.

Bibliography. Breed & Aplin (1995), Flannery (1995b), Helgen (2007a), Musser & Carleton (2005), Smales (2015), Steppan & Schenk (2017).