677.

Rio de Janeiro Arboreal Rat

Phaenomys ferrugineus

French: Phaenomys ferrugineux / German: Rio-de-Janeiro-Ratte / Spanish: Rata arboricola de Rio de Janeiro

Other common names: Rusty Phaenomys

Taxonomy. Oryzomys ferrugineus Thomas, 1894, “Rio [de] Janeiro,” Rio de Janeiro State, Brazil.

Phaenomys ferrugineus is the type species of the genus. Monotypic.

Distribution. Known from a handful of localities in SE Brazil (Minas Gerais, Rio de Janeiro, and Sao Paulo states).

Descriptive notes. Head-body 143-170 mm, tail 187-199 mm, ear 20 mm, hindfoot 31 mm; weight 50-75 g. The Rio de Janeiro Arboreal Rat has moderately large, long, dark brown, and slightly hairy tail, with inconspicuous hair pencil at tip. Dorsal pelage is dense and long, varying from rufous to rust orange; venter is pure white or white washed with buff or rufous. Ears are brownish, covered by rusty hairs. Mystacial vibrissae are thick and long, extending beyond ears. Hindfeet are covered in metatarsal region by yellowish to pale rusty hairs, with proximal part of hindfeet rust and distal part dirty white. Chromosomal complement is 2n = 78, FN = 114.

Habitat. Montane Atlantic Forest at elevations of 900-1550 m.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. The Rio deJaneiro Arboreal Ratis nocturnal. Usually reported as arboreal, but two individuals were recently trapped on the ground in herbaceous vegetation.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Vulnerable on The IUCNRed List. The Rio deJaneiro Arboreal Rat occurs in only 12,000 km? and is known from fewer than ten locations. Extent and quality of its habitat continue to decline.

Bibliography. Bonvicino & Percequillo (2008), Bonvicino et al. (2001), Pardinas, D'Elia et al. (2014), Passamani et al. (2011), Percequillo (2015a), Thomas (1894), Vaz (2000).