Callicebus oenanthe, Thomas, 1924

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Phitheciidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 432-483 : 460

5.

San Martin Tit

Callicebus oenanthe

French: Titi du Mayo / German: Anden-Springaffe / Spanish: Titi andino

Other common names: Andean Titi Monkey, Isabelline Titi, Rio Mayo Titi, Rio Mayo Titi Monkey, San Martin Titi Monkey

Taxonomy. Callicebus oenanthe Thomas, 1924 ,

Moyobamba, San Martin, Peru, altitude 840 m.

C. oenanthe is a member of the C. donacophilus species group. Monotypic.

Distribution. W Amazon Basin in N Peru, mainly in the upper Rio Mayo Valley, but extending S possibly as far as the Rio Huayabamba.

Descriptive notes. Head-body 30-32 cm, tail 38-40 cm (males) and 36-38 cm (females); weight c.800 g as for other members of the donacophilus species group. Pelage of the San Martin Titi is dark brown agouti or light brown agouti. It has a pale malar stripe, and a buffy or whitish forehead blaze is usually present, continuous with a similarly colored, long circumfacial crest. Sideburns and outer surfaces of limbs are agouti, and underparts (including inner surfaces of limbs) are a contrasting orange. Tail is dark brown agouti. There are differences in pelage coloration among subpopulations.

Habitat. Montane cloud forest at elevations of 750-950 m. The San Martin Titi can be found in a variety of distinct vegetation formations, including inundated areas with “aguajales” ( Mauritia flexuosa palm-dominated forests) and “renacales” (Ficus-dominated forests), low secondary forest, Cecropia-dominated stands, bamboo stands, viney thickets, and fruit crops.

Food and Feeding. A recent field study of one group of the San Martin Titi in the upper Mayo Valley revealed a frugivorous diet (54% fruit), with a relatively large contribution of arthropod prey (22%), along with seeds, leaves, and flowers. While this degree of frugivory is typical of titis, this was the highest proportion of animal prey recorded to date for any titi species, although similar proportions have been recorded in the Brown Titi ( C. brunneus ) and the Yellow-handed Titi ( C. lucifer ).

Breeding. A birth of a San Martin Titi was recorded in May. Titis, in general, form monogamous breeding pairs, in which the male provides parental care by carrying the single offspring.

Activity patterns. The San Martin Titi is diurnal and arboreal. They live in small, pairbonded, territorial groups that engage in duet vocalizations mainly during the early part of the day. One study recorded relatively high levels of foraging (35% feeding and foraging) compared with othertiti species, except the Masked Titi ( C. personatus ). Resting took up ¢.33% of the activity budget, followed by traveling (22%) and engaging in social behavior (10%).

Movements, Home range and Social organization. One study group of San Martin Tits in an isolated fragment of forest contained an adult breeding pair and 2-3 immature offspring, which is typical of the group composition oftitis. This group of San Martin Tits occupied a home range of 2-5 ha, with mean daily movements of ¢.650 m. Relatively high densities have been recorded in other fragmented forests, with a group of eleven individuals being observed at onesite. It is unclear if this was a permanent group or a temporary meeting of two groups.

Status and Conservation. CITES Appendix II. Classified as Critically Endangered on The IUCN Red List. The San Martin Titi is found in a small and isolated part of the western Amazon Basin, which nevertheless suffers intensive anthropogenic pressures and widespread deforestation. San Martin Titis are also hunted and captured for the local pet trade. Most of the overall population of the San Martin Titi is now restricted to small, isolated fragments of habitat. The establishment of ecological corridors is a priority conservation action. Privately owned reserves and indigenous lands may play an essential role in the conservation of the San Martin Titi over the long term.

Bibliography. Aldrich (2006), Aquino & Encarnacion (1994b), Boveda-Penalba et al. (2009), Deluycker (2006, 2007b), Hershkovitz (1988, 1990), Mark (2003), Norconk (2011), Rowe & Martinez (2003), Veiga, Béveda-Penalba et al. (2008), Vermeer et al. (2011).

Figures

On following pages: 4. Olallas’ Titi (Callicebus olallae); 5. San Martin Titi (Callicebus oenanthe); 6. Coppery Titi (Callicebus cupreus); 7. Red-crowned Titi (Callicebus discolon; 8. Ornate Titi (Callicebus ornatus); 9. Chestnut-bellied Titi (Callicebus caligatus); 10. Doubtful Titi (Callicebus dubius); 11. Stephen Nash's Titi (Callicebus stephennashi); 12. Caqueta Titi (Callicebus caquetensis);, 13. Ashy Titi (Callicebus cinerascens); 14. Hoffmanns's Titi (Callicebus hoffmannsi); 15. Lake Baptista Titi (Callicebus baptista); 16. Red-bellied Titi (Callicebus moloch).

Distribution. W Amazon Basin in N Peru, mainly in the upper Rio Mayo Valley, but extending S possibly as far as the Rio Huayabamba.