383.

Keays’s Rice Rat

Nephelomys keaysi

French: Néphélomys de Keays / German: Keays-Reisratte / Spanish: Rata arrocera de Keays

Other common names: Keays's Nephelomys, Keays's Oryzomys

Taxonomy. Oryzomys keaysi J. A. Allen, 1900, “Juliaca, Peru, altitude 6000 ft [= 1829 m].” Corrected byJ. A. Allen in 1901 to “Inca Mines [= Santo Domingo Mine], about 200 miles [= 322 km] northeast of Juliaca, on the east side of the Andes, on the Inambary River [= Rio Inambari],” Puno, Peru.

This species is monotypic.

Distribution. E Andean slopes from C Peru SE to C Bolivia.

Descriptive notes. Head-body 125-165 mm, tail 146-207 mm, hindfoot 32-34 mm. No specific data are available for body weight. Keays’s Rice Rat is moderately large, with dense, long, and lax dorsal fur, ocherous to buffy ocher and intensely grizzled with brown. Venter is grayish, whitish, or rarely yellowish, without white pectoral or gular patches. Ears are large, with fine blackish hair on surfaces. Tail is longer than head-body length and mainly unicolored. Interorbital region of skull is slightly to strongly divergent posteriorly, with supraorbital margins squared to strongly beaded. Alisphenoid strut is present in most specimens. Chromosomal complement is 2n = 80, FN = 92-94.

Habitat. Primary and secondary montane and cloud forests on Andean eastern slopes at elevations of 1000-2600 m. Keays’s Rice Rat has not been recorded in cultivated areas. In Yanahuaya (Peru), it inhabits semi-leafy humid forests, with thin, medium, and large trees up 15 m, covered with lianas; soil is silty, very moist, and full oflitter and grass; and slopes are moderate to steep.

Food and Feeding. No information.

Breeding. Pregnant Keays’s Rice Rats were captured in November, with three embryos, at Santa Cruz, Peru; females with 4-5 uterine scars were observed in July east of Paucartambo, Peru.

Activity patterns. Keays’s Rice Rat is nocturnal and terrestrial.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Allen (1901b), Eisenberg & Redford (1999), Pacheco, Cadenillas et al. (2009), Pacheco, Marquez et al. (2011), Patton et al. (1990), Percequillo (2015g), Zeballos (2016a).