Rhynchocyon petersi, Bocage, 1880

Russell A. Mittermeier & Don E. Wilson, 2018, Macroscelididae, Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona: Lynx Edicions, pp. 206-234 : 228

4.

Black-and-rufous Sengi

Rhynchocyon petersi

French: Sengi de Peters / German: RotschulterRisselhindchen / Spanish: Sengi de Peters

Other common names: Black-and-rufous Elephant-shrew, Peters’s Elephant-shrew, Peters’'s Sengi, Zanj Elephantshrew, Zanj Sengi

Taxonomy. Rhynchocyon petersi Bocage, 1880 ,

“ Zanzibar ,” Tanzania. Restricted by G. Dollman in 1912 to “ East Africa, Zanzibar being used in the original description for the whole district and not for the island.”

Two subspecies are recognized.

Subspecies and Distribution.

R.p.petersiBocage,1880—SEKenyaandETanzania(EasternArcMtsandcoastalforests).

R. p. adersi Dollman, 1912 — Unguja and Mafia Is (Zanzibar Archipelago), off Tanzania.

Descriptive notes. Head—body 252-290 mm, tail 218-252 mm, ear 25-31 mm, hindfoot 65-74 mm; weight ¢.540 g. Tail of the Black-and-rufous Sengi is ¢.85% of headbody length and is proximally thick and distally tapered; it is nearly hairless with orange-brown skin and can have subterminal white band. Pelage on shouldersis orange, rufous-orange, or maroon (with geographical variation), transitioning to black on back and rump. Pinnae are nearly hairless, with orange-brown skin. Color pattern on shoulders, back, and rump and color of ear skin are collectively diagnostic. Head and snout are bright rufous or orange-brown. Venter is orange to rufous-orange. Some individuals have indistinct dorsal checker patterns, reminiscent of the Chequered Sengi ( R. cirnei ). Snout is long and flexible. Females have two posterior, two intermediate, and no anterior nipples; males have no nipples. Four digits are present on each manus and pes; pollex and hallux are absent. Fifth manual digit is relatively short and has only two phalanges. Post-anal gland is well developed, and pectoral gland is absent. Dental formulais10-1/3,C1/1,P 4/4, M 2/2 (x2) = 34-36. Upper canines are relatively large. Presence of diminutive upper incisoris variable. Palatal foramina are absent. Postorbital processes are present. Karyotype is unknown.

Habitat. Semideciduous and evergreen forests, dense woodlands, coral rag scrub, and abandoned agricultural lands (closed canopies and dense leaf litter always present).

Food and Feeding. The Black-and-rufous Sengi almost certainly strictly eats invertebrates and mostly arthropods. In Nkuka Forest, Tanzania, some individuals eat soldier ants (Dorylus).

Breeding. The Black-and-rufous Sengi is monogamous; breeding occurs year-round. Gestation is c.40 days, interbirth interval is ¢.80 days, and litters have 1-2 young. Newborns are semi-precocial, remain in a nest for c.2 weeks, and are then weaned.

Activity patterns. Black-and-rufous Sengis are fully terrestrial and exclusively diurnal. Forest-floor nests are built from leaf litter.

Movements, Home range and Social organization. The Black-and-rufous Sengi is presumably similar to other species of Rhynchocyon . Each member of a male-female pair probably spends most of its time independently.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Blackand-rufous Sengi was previously classified as Vulnerable and Endangered. Population trend is decreasing.

Bibliography. Allen & Loveridge (1927), Baker et al. (2005), Carlen et al. (2017), Corbet & Hanks (1968), Coster & Ribble (2005), Dollman (1912), Dumbacheret al. (2014), Evans (1942), Hoffmann et al. (2016), Hollister (1918), Loveridge (1922), Olbricht & Stanley (2009), Rathbun (2009, 2013f), Rovero et al. (2008).

Figures

1. Golden-rumped Seng (Rhynchocyon chrysopygus), 2. Chequered Sengi (Rhynchocyon cirne), 3. White-tailed Sengi (Rhynchocyon stuhlmanni), 4. Black-and-rufous Sengi (Rhynchocyon petersi), 5. Gray-faced Sengi (Rhynchocyon udzungwensis), 6. Namib Round-eared Sengi (Macroscelides flavicaudatus), 7. Karoo Round-eared Sengi (Macroscelides proboscideus), 8. Etendeka Round-eared Sengi (Macroscelides micus), 9. Four-toed Sengi (Petrodromus tetradactylus), 10. North African Sengi (Petrosaltator rozeti), 11. Rufous Sengi (Elephantulus rufescens), 12. Somali Sengi (Elephantulus revoulii), 13. Dusky-footed Sengi (Elephantulus fuscipes), 14. Short-snouted Sengi (Elephantulus brachyrhynchus), 15. Dusky Sengi (Elephantulus fuscus), 16. Bushveld Sengi (Elephantulus intufi), 17. Western Rock Sengi (Elephantulus rupestris), 18. Eastern Rock Sengi (Elephantulus mywrus), 19. Cape Rock Sengi (Elephantulus edwardii), 20. Karoo Rock Sengi (Elephantulus pilicaudus)

Subspecies and Distribution. R.p.petersiBocage,1880—SEKenyaandETanzania(EasternArcMtsandcoastalforests). R. p. adersi Dollman, 1912 — Unguja and Mafia Is (Zanzibar Archipelago), off Tanzania.