Spilocuscus rufoniger (Zimara, 1937)

Russell A. Mittermeier & Don E. Wilson, 2015, Phalangeridae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 456-497 : 495

24.

Black Spotted Cuscus

Spilocuscus rufoniger

French: Phalanger noir et roux / German: Schwarzfleck-Tupfelkuskus / Spanish: Cuscus rojinegro

Other common names: Black-spotted Phalanger

Taxonomy. Phalanger maculatus rufoniger Zimara, 1937 ,

“ Sattelberg [= Huon Gulf],” Morobe Province, Papua New Guinea.

No subspecies are currently recognized, but a review of variation across the distribution of this species would be worthwhile. Monotypic.

Distribution. N New Guinea, from the Bird’s Head (= Vogelkop) Peninsula in the W to the Huon Peninsula in the E, and most probably including Yapen I. There are a small number of records from S New Guinea, from Lorentz (= Noord) River area and headwaters of Fly River.

Descriptive notes. Head—body 58-69 cm (mean 61-9 cm), tail 45-65 cm (mean 56-3 cm); weight 5.5-6.6 kg (mean 6-2 kg). The Black Spotted Cuscus is the largest phalangerid in New Guinea and could only be confused with the Common Spotted Cuscus (S. maculatus ), from which it is nevertheless easily distinguished. Skins of male Black Spotted Cuscuses have cream undersides and cream base colors to dorsa, on which are overlaid intensely blackish (jet-black to maroon) spotting or blotching on mid-backs and upper hindlegs and intensely red-orange or golden fur on face, head, nape, shoulders, hands, feet, and sometimes body of limbs; tail is golden or whitish; and white fur of underside of throat and chin often extends as a crescent to cheeks and ears, contrasting with intense color of head. Female color is the same, except that back is not black-spotted but instead marked with a black saddle that extends over mid-back and hindlimbs. This pelage pattern can never be confused with adult pelage pattern of the Common Spotted Cuscus from northern New Guinea, in which individuals are only cream-colored or orange-brown and never have blackish or even dark-brown tones in mature pelage. Forequarters of Black Spotted Cuscuses from Bird's Head Peninsula are often more golden than deep red. Juvenile pelage is rather uniform red-brown in both sexes. Skull and teeth of the Black Spotted Cuscus are instantly identifiable. Skull is large (condylobasal length 107-125 mm). There are usually three unicuspids in lower jaw, spicule-like second premolar (dP?) is typically retained in adult dentition, and molars are more massive and more weakly crenulate than in other species of phalangerids. As in the Waigeo Spotted Cuscus (S. papuensis ), on the anterior margin of the orbit, frontal typically contacts maxilla (highly variable in other taxa).

Habitat. Undisturbed primary forests from sea level to elevations of ¢.1200 m. The Black Spotted Cuscus is considered uncommon throughoutits distribution.

Food and Feeding. There is no specific information available for this species, but the Black Spotted Cuscus is presumably frugivorous—folivorous and is said to feed on acorns of Lithocarpus (Fagaceae) .

Breeding. There is no specific information available for this species, but the Black Spotted Cuscus produces one offspring at a time.

Activity patterns. Black Spotted Cuscuses sleep exposed on branches high in the canopy and have been observed to be active during the day and night. Predators include large pythons.

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. Classified as Critically Endangered on The IUCN Red List. The Black Spotted Cuscus is threatened by habitat loss, expanding human populations and impacts, and hunting, including spread of firearms. It has undergone a suspected population decline in excess of 80% over three generations (c.15 years) due to levels of exploitation and habitat loss, including impacts from oil palm and logging concessions. There are no recent records of the Black Spotted Cuscus from the Bird’s Head or Huon peninsulas, and it may be extinct in these and other regions of former occurrence. In-depth field assessments are needed to understand the full extent of the current distribution of the Black Spotted Cuscus.

Bibliography. Feiler (1978), Flannery (1995a), George (1987), Helgen (2007c), Leary, Singadan, Menzies, Helgen, Allison et al. (2008c), Zimara (1937).

Figures

11. Peleng Cuscus (Phalanger pelengensus), 12. Moluccan Cuscus (Phalanger ornatus), 13. Gebe Cuscus (Phalanger alexandrae), 14. Obi Cuscus (Phalanger rothschildi), 15. Ground Cuscus (Phalanger gymnotis), 16. Woodlark Cuscus (Phalanger lullulae), 17. Northern Common Cuscus (Phalanger orientalis), 18. Eastern Common Cuscus (Phalanger intercastellanus), 19. Southern Common Cuscus (Phalanger mimicus), 20. Telefomin Cuscus (Phalanger matanim), 21. Stein’s Cuscus (Phalanger vestitus), 22. Silky Cuscus (Phalanger sericeus), 23. Mountain Cuscus (Phalanger carmelitae), 24. Black Spotted Cuscus (Spilocuscus rufoniger), 25. Waigeo Spotted Cuscus (Spilocuscus papuensis), 26. Admiralty Spotted Cuscus (Spilocuscus kraemeri), 27. Blue-eyed Spotted Cuscus (Spilocuscus wilsoni), 28. Common Spotted Cuscus (Spilocuscus maculatus), 29. Australian Spotted Cuscus (Spilocuscus nudicaudatus)

Distribution. N New Guinea, from the Bird’s Head (= Vogelkop) Peninsula in the W to the Huon Peninsula in the E, and most probably including Yapen I. There are a small number of records from S New Guinea, from Lorentz (= Noord) River area and headwaters of Fly River.