Myoprocta acouchy (Erxleben, 1777)

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Dasyproctidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 440-461 : 460-461

14.

Red Acouchy

Myoprocta acouchy

French: Agouti rouge / German: Rotes Acouchi / Spanish: Acuchi rojo

Taxonomy. Cavia acouchy Erxleben, 1777 ,

“Habitat vulgaris in Guiania reliquaque America australi.” Fixed by neotype selection by R. S. Voss and colleagues in 2001 to “Paracou, French Guiana.”

Mpyoprocta exilis is a synonym of M. acouchy . Validity of acouchy vs. exilis has yet to be tested by analyses of any type of character set. The taxon M. leptura is included in M. acouchy . Monotypic.

Distribution. The Guianas and N Brazil (E of the Rio Branco and N of the Amazon River); it has also been reported in two localities between the Rio Madeira and Rio Tapajos S of the Amazon.

Descriptive notes. Head-body 335-390 mm, tail 51-78 mm, ear 25-40 mm, hindfoot 90-104 mm; weight 1.1-4 kg. Upper parts of the Red Acouchy are dark chestnut-red or orange on sides and legs, grizzled with black and some yellow on crown and neck. Mid-back and rump are glossy black or very red. Rump hairs are long and straight, overhanging rear of body in a fringe. Tail is short and slender, white below and small white tuft at tip.

Habitat. Mature, lowland evergreen tropical forest, less common in extensive areas of secondary forest. The Red Acouchy can exist in altered areas close to natural forest.

Food and Feeding. The Red Acouchy eats fruits, predominantly pulp, followed by seeds and exocarps; other foods include insects, comprising less than 1% of the diet. Diet varies seasonally, depending on number offruiting plant species and overall fruit production and nutritional needs associated with reproduction. Seeds are collected and scatter-hoarded by burying, with caches often more than 100 m from the tree that dropped them. Food is buried in small caches throughout an entire home range.

Breeding. Reproduction of the Red Acouchy is strongly seasonal, with more than onehalf of all births concentrated in November—January, during the period when numbers of fruiting tree species and individuals of these species begin their annual fruiting. Litters have 1-3 young, with a median of two young per pregnancy. Estrous cycle averages c.42 days, and gestation is ¢.99 days. Juvenile sex ratio is skewed in favor of males, but adult sex ratio is near 1:1, resulting from increased risks taken by juvenile males during dispersal.

Activity patterns. Red Acouchys are strictly diurnal, with most activity confined to morning hours. At night, they rest in nests of leaves, usually inside a hollow log. They are rarely found in burrows made by other species. When alarmed, Red Acouchys stamp their hindfeet and emit a squeal or whistle followed by short series of highpitched chirps.

Movements, Home range and Social organization. Basic social unit of the Red Acouchy is a family of a monogamous pair and their immediate offspring. Each member may live alone within individual home ranges that have little overlap. These home ranges have heavily frequented areas and many resting sites, often located in hollow logs that consist of a single nest in current use and several older leaf-heaps. Sizes of home ranges and level of individual activity decrease in the dry season when food resources are most scarce. Familial units are widely separated, so intergroup interactions are rare. Home ranges are 0-65—1-2 ha. Females prefer dense habitat, and males prefer open forest, which becomes more evident during the dry season.

Status and Conservation. Classified as Least Concern on The IUCN Red List. In certain locations, the Red Acouchy is overhunted, causing local extirpation in some areas of Suriname and French Guiana. Due to their preference for open forest, males are harvested more often than females. Some indigenous people in Brazil keep Red Acouchys as pets.

Bibliography. Catzeflis et al. (2008a), Dubost (1988), Dubost & Henry (2006), Dubost et al. (2005), Emmons (1997a), Jansen etal. (2004), Jorge (2008), Patton & Emmons (2015a), Voss et al. (2001), Woods & Kilpatrick (2005).

Figures

On following pages: 4. Roatan Island Agouti (Dasyprocta ruatanica); 5. Black Agouti (Dasyprocta fuliginosa); 6. Common Red-rumped Agouti (Dasyprocta leporina); 7. Guamara Agouti (Dasyprocta guamara); 8. Orange Agouti (Dasyprocta croconota); 9. Black-rumped Agouti (Dasyprocta prymnolopha); 10. lack’s Red-rumped Agouti (Dasyprocta iacki); 11. Brown Agouti (Dasyprocta variegata); 12. Kalinowski's Agouti (Dasyprocta kalinowskii); 13. Azara's Agouti (Dasyprocta azarae); 14. Red Acouchy (Myoprocta acouchy); 15. Green Acouchy (Myoprocta pratt).

Distribution. The Guianas and N Brazil (E of the Rio Branco and N of the Amazon River); it has also been reported in two localities between the Rio Madeira and Rio Tapajos S of the Amazon.