403.

McConnell’s Rice Rat

Euryoryzomys macconnelli

French: Oryzomys de McConnell / German: McConnell-Reisratte / Spanish: Rata arrocera de McConnell

Other common names: McConnell’s Euryoryzomys, MacConnell’'s Oryzomys

Taxonomy. Oryzomys macconnelli Thomas, 1910, “River Supinaam, a tributary of the lower Essequibo,” Demerara, British Guiana (= Guyana).

Euryoryzomys macconnelli is the type species of the genus. Monotypic.

Distribution. Mostly in Amazon Basin, including S Colombia, S Venezuela, the Guianas, E Ecuador, E Peru, and Brazil.

Descriptive notes. Head-body 130-166 mm, tail 124-175 mm, hindfoot 32-37 mm. No specific data are available for body weight. McConnell’s Rice Rat is mediumsized, with very dense, lax, and long fur; dorsum varies from orange to reddish brown. Tail is ¢.104% of head-body length. Compared to the congeneric and sympatric Elegant Rice Rat ( E. nitidus), McConnell’s Rice Rat has narrower zygomatic plates, shallower zygomatic notches, wider interorbital region, shorter and wider incisive foramina teardrop in shape, and longer bony palate. It also no alisphenoid struts, M, has an ectolophid, and capsular process is not evident. Chromosomal complementis 2n = 76, FN = 85 on left bank of Rio Negro, 2n = 58, FN = 90 on right bank of Rio Negro, and 2n = 64, FN = 70 south of the Amazon River in western Brazil, Ecuador, and Peru.

Habitat. Primary tropical evergreen rainforest, from sea level to elevations of 1500 m in the tepuis of Venezuela and Andean foothills of Peru.

Food and Feeding. No information.

Breeding. Pregnant and lactating McConnell’s Rice Rats were recorded during rainy and dry seasons. Embryo counts 2—4 in western Brazilian Amazon.

Activity patterns. McConnell’s Rice Ratis terrestrial, and trapping data suggests nocturnal activity.

Movements, Home range and Social organization. Densities vary from 0-09 ind/ha to 0-38 ind/ha.

Status and Conservation. Classified as Least Concern on The IUCN Red List. McConnell’s Rice Rat can be an indicator of environmental quality because it is unfavourably affected by forest fragmentation.

Bibliography. Musser & Carleton (2005), Musser, Carleton et al. (1998), Patton, Catzeflis et al. (2016e), Patton, da Silva & Malcolm (2000), Percequillo (2015d).