Aotus nancymaae Hershkovitz 1983

9. Ma’s Night Monkey Aotus nancymaae French: Douroucouli du Loreto / German: Nancy-Ma-Nachtaffe / Spanish: Mico nocturno de Nancy Ma Other common names: Nancy Ma's Night Monkey, Nancy Ma's Owl Monkey Taxonomy. Aotus nancymai Hershkovitz, 1983, right bank of Rio Samiria above Estacion Pithecia, Reserva Nacional Pacaya-Samiria, Loreto, Peru, elevation ¢.130 m. This species is monotypic. Distribution. W Brazil (S of the Rio Solimoes from the Rio Javari on the Peruvian border E possibly as far as the Rio Jandiatuba) and NE Peru (from the Javari W to the Rio Huallaga), also found N of the Maranon in an enclave between the lower rios Tigre and Pastaza to c.03° S. Descriptive notes. Head-body 29-34 cm, tail 35-42 cm; weight 794-5 g (male average, n = 32) and 780-2 g (female average, n = 24). Ma’s Night Monkey is a red-necked species, with a diploid chromosome number of 54. Upperparts of the body are grayish-agouti, with a darkened mid-dorsal zone and a pale orange underside; the latter color extends up the sides of the neck and inner limbs. Proximal part of the tail is also orange with, usually, a blackish stripe above; the underside of the tail is blackish. Face is grayish-white, crown stripes are narrow and dark brown, and sides of the throat and jaw are colored like the body. An interscapular whorl is absent. Habitat. [Lowland tropical forest including seasonally flooded forest at elevations of 60-130 m. Densities of Ma’s Night Monkeys are lower in terra firma forest because of a relative paucity of tree holes, their preferred sleeping sites, compared with lowland swamp and seasonally inundated forests. Trees in terra firma forest are predominantly hardwoods that provide fewer hollows for sleeping. Lowland swamp and inundated forests have a predominance of softwood that more easily form hollows and abundant dense vine tangles that these monkeys also use as sleeping sites. Food and Feeding. In captivity, Ma’s Night Monkeys eat insects, geckos,lizards, and on one occasion, a small bird. Food sharing is prevalent in captivity. Breeding. A peak in births has been estimated to be between December and March in the wet season, but captive populations breed throughout the year when photoperiod is kept constant. Age at first reproduction is about 40 months. Single offspring are the rule, and twinning in captivity only occurred in one of 169 births in one study and one in 287 births in a second study. Interbirth intervals in captive females are 9-11 months. In captivity, pregnant females may mate. Activity patterns. Ma’s Night Monkey is nocturnal and arboreal. Movements, Home range and Social organization. Field research on the Rio Tahuayo, north-eastern Peru, in 1978-1979 found social groups of 2-5 individuals (average 3-4), including a breeding pair and its offspring. In one instance, a third adult was seen traveling some 20-30 m from a group; it was eventually attacked and chased off by the breeding pair. Density at Rio Tahuayo was estimated at 8-7 groups/km? or 25 ind/km?. An analysis of the population structure found a lack ofjuveniles (450-575 g), indicating poor survival ofthis age category. Density estimates obtained for Ma’s Night Monkey in nine other localities from 1982 to 1985 were 3-9-13-2 groups/km? or 16-54-2 ind/km?. Status and Conservation. CITES Appendix II. Classified as Least Concern on The IUCN Red List. There are no major identified threats, but their capture for use in medical research continues. Peru banned trade in primates in 1973 and became a signatory to CITES in 1975. Between 1994 and 2007, registered exports of Ma’s Night Monkey from Peru totaled 1059 animals, but it is still being exported illegally, with Peruvian and Brazilian Ma’s Night Monkeys and Black-headed Night Monkeys (A. nigriceps) appearing in Colombia where they do not otherwise occur. Ma’s Night Monkey occurs in the Jutai-Solimoes Ecological Station in Brazil and Pacaya-Samiria National Reserve and ACR Comunal Tamshiyacu Tahuayo in Peru. Bibliography. Aquino & Encarnacion (1986a, 1986b, 1988, 1994a), Aquino et al. (1990, 1992), Bolen & Green (1997), Cornejo & Palacios (2008a), Feged et al. (2002), Ford (1994a, 1994b), Gozalo & Montoya (1990), Held & Wolfle (1994), Hershkovitz (1983), Kumamoto & Houck (2001), Malaga, Weller, Buschbom et al. (1997), Mélaga, Weller, Montoya et al. (1991), Maldonado et al. (2009), Nino-Vasquez et al. (2000), Pieczarka et al. (1992), Wolovich & Evans (2007), Wolovich et al. (2008a, 2010), Wright (1981, 1989, 1994).Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Aotidae, pp. 414-431 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on pages 429-430, DOI: 10.5281/zenodo.572696