Pithecia irrorata, Gray, 1842

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 : 476

34.

Gray's Bald-faced Saki

Pithecia irrorata

French: Saki a téte chauve / German: Nacktgesichtsaki / Spanish: Saki gris

Other common names: Bald-faced Saki, Gray Monkey Saki, Gray Saki, Rio Tapajos Saki; Vanzolini's Bald-faced Saki (vanzolinii)

Taxonomy. Pithecia irrorata Gray, 1842 ,

“Tropical America” or “Brazils” (a common term for the Amazon in the 1800s).

P. Hershkovitz in 1987 indicated that the holotype of P. irrorata was a pet of the crew of the HMS Sulphur, obtained during a survey on the Pacific coast of South America in 1836-1839. Hershkovitz speculated that the animal was purchased in Rio de Janeiro, but there is no evidence that the HMS Sulphur expedition went there, and it would seem more probable that the animal was obtained in Peru. The taxonomy of Pithecia followed here is that proposed by Hershkovitz in 1987. A taxonomic revision currently being undertaken by L. K. Marsh will provide a broader and more accurate understanding of the diversity and distributions ofthe sakis. Two subspecies recognized.

Subspecies and Distribution.

P.i.wrrorataGray,1842—Brazil(fromtheriosJurua-TarauacaEtotheriosTapajos-Juruena,andStotheRioGuaporé),NBolivia(NoftheRioMadredeDios),andSEPeru(fromtheupperRioPurus,WoftheRioUrubamba,andStotheRioTambopata);itdoesnotoccurbetweenthelowerPurusandtheRioJurua,thedomainoftheBuftySaki(P.albicans).

P. i. vanzolinii Hershkovitz, 1987 — First described from Santa Cruz on the Rio Eiru (S tributary of the Rio Jurua), and believed to occur between the S (right) bank of the upper Rio Jurua and the S bank of the Rio Tarauaca in the SW of the Amazonas and Acre states, but there are very few documented locations.

Descriptive notes. Head—body 37.5-49 cm (males) and 36-53 cm (females), tail 42— 51-4 cm (males) and 33-50 cm (females); weight 2-9 kg (males) and 2.2-2 kg (females) for the nominate subspecies (P. i. #rrorata). Head—body 36—41-5 cm (males) and 35.5-42 cm (females), tail 40-52 cm (males) and 46-52 cm (females); no weights available for “Vanzolini’s Bald-faced Saki” (P. i. vanzolinii). Male Gray’s Bald-faced Sakis are large with grizzled pelage, a bright white fringe, a buffy to orange ruff, and dark pink, hairless facial skin. Overall grayish pelage of female Gray’s Bald-faced Sakisis similar to female Equatorial Sakis ( P. aequatorialis ), but female Gray’s Bald-faced Sakis have a black fringe around their faces. Male Gray’s Bald-faced Sakis are, on average, slightly larger than females. Males are blackish overall, with little white stippling, instead with cream to buffy blonde forearms and legs. Faces of males are bare with cream malar lines, and females have black hair around their faces. In contrast, Vanzolini’s Bald-faced Sakis have tufts of short white hair (snips) in the middle of their foreheads.

Habitat. Lowland terra firma forest and white water, seasonally flooded forest (varzea).

Food and Feeding. In a study in Peru, the diet of Gray's Bald-faced Saki contained seeds (83%), fleshy fruits (15%), flowers (0-5%), and leaves (1-5%). Principal plant families in the diet were Moraceae , Sapotaceae , Fabaceae , and Chrysobalanaceae .

Breeding. There is no information available forthis species.

Activity patterns. Gray’s Bald-faced Sakiis diurnal and arboreal. Like other Amazonian sakis, they move through upperstrata of the forest canopy.

Movements, Home range and Social organization. Group sizes of 2-5 Gray’s Bald-faced Sakis have been recorded in Brazil and Bolivia.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List, including the nominate subspecies irrorata , but the subspecies vanzolinii is listed as Data Deficient. Nevertheless, because taxonomy their poorly understood, the real status of Gray’s Bald-faced Saki and its subspecies is unclear, but at least the nominate subspecies is apparently wide ranging. Very little is known of Vanzolini’s Baldfaced Saki , which evidently has a very restricted distribution.

Bibliography. Buchanan-Smith et al. (2000), Hershkovitz (1979b, 1987a), Norconk (2011), Norconk & Setz (2013), Palminteri et al. (2013).

Figures

On following pages: 20. Madidi Titi (Callicebus aureipalatii); 21. Medem'’s Titi (Callicebus medemi); 22. White-collared Titi (Callicebus torquatus); 23. White-chested Titi (Callicebus lugens); 24. Yellow-handed Titi (Callicebus lucifen; 25. Rio Purus Titi (Callicebus purinus); 26. Rio Jurué Collared Titi (Callicebus regulus); 27. Black-fronted Titi (Callicebus nigrifrons); 28. Masked Titi (Callicebus personatus); 29. Southern Bahian Titi (Callicebus melanochir); 30. Blond Titi (Callicebus barbarabrownae); 31. Coimbra-Filho's Titi (Callicebus coimbral).

Subspecies and Distribution. P.i.wrrorataGray,1842—Brazil(fromtheriosJurua-TarauacaEtotheriosTapajos-Juruena,andStotheRioGuaporé),NBolivia(NoftheRioMadredeDios),andSEPeru(fromtheupperRioPurus,WoftheRioUrubamba,andStotheRioTambopata);itdoesnotoccurbetweenthelowerPurusandtheRioJurua,thedomainoftheBuftySaki(P.albicans). P. i. vanzolinii Hershkovitz, 1987 — First described from Santa Cruz on the Rio Eiru (S tributary of the Rio Jurua), and believed to occur between the S (right) bank of the upper Rio Jurua and the S bank of the Rio Tarauaca in the SW of the Amazonas and Acre states, but there are very few documented locations.