Sciurocheirus alleni
Creators: name: Russell A. Mittermeier
name: Anthony B. Rylands
name: Don E. Wilson
Publisher: name: Lynx Edicions
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Primates
Galagidae
Sciurocheirus
Sciurocheirus alleni

description: 12.
Bioko Squirrel Galago
Sciurocheirus alleni
French: Galago d'Allen / German: Bioko-Buschwaldgalago / Spanish: Géalago ardilla de Bioko
Other common names: Allen's Bushbaby, Allen's Galago, Bioko Allen's Bushbaby
Taxonomy. Galago alleni Waterhouse, 1838,
Equatorial Guinea, Fernando Po (= Bioko).
In 1863, J. Gray placed this species in a separate genus, Sciurocheirus (squirrel galagos), but more recently, some authors have placed it as a subgenus of Galago. It is distinct from the lesser galagos in a number ofits characters, including its unique locomotory anatomy and behavior. It has a long muzzle, long fingers, rusty-red pelage, flufty tail, and nasal bones that are not truncated posteriorly. Genetically,its sister genus is Otolemur. Formerly three subspecies were recognized, but the gabonensis and cameronensis forms have been elevated to full species. Further variation and species may still be recognized within the genus. Monotypic.
Distribution. Endemic to Bioko I.
Descriptive notes. Head-body 20-28 cm, tail 23-30 cm; weight 300-410 g. The Bioko Squirrel Galago is dark brownish-gray above, often with a heavy tinge of red, and reddish limbs. The underside is pale grayish-white, sometimes with a yellow tone. There is a black mask, made up of broad black eye-rings over the otherwise light gray face. The muzzle protrudes with a pale gray stripe. The tail is black, never with a white tip, and bushy throughout, like a squirrel’s tail. Ears are relatively short with a pale gray ring around their bases.
Habitat. Primary montane forest.
Food and Feeding. The Bioko Squirrel Galago is frugivorous, consuming mainly fruits and gums, supplemented with young leaves and certain types of wood. Some invertebrates and frogs are also eaten, which are caught by hand rather than by mouth. It perches above ant trails to eat them as they move. It forages in the low to mid-canopy and on the ground.
Breeding. Births occur year-round, with a noticeable peak in January. Pregnant and lactating females have been observed on Bioko Island in March. One (sometimes two) young are born per year, which the mother carries in her mouth for the first six weeks.
Activity patterns. The Bioko Squirrel Galago is nocturnal and arboreal. Like other bushbabies, it has elongated hindlimbs and a long tail for vertical clinging and leaping. It can leap 2—4 m between vertical supports.
Movements, Home range and Social organization. Regular vocal contact is common among individual Bioko Squirrel Galagos when they are dispersed. These contact calls help in species identification. A harsh, low-frequency croak used for long distance contact is common to all squirrel galagos. Long whistles given as single units, or in phrases of one to six descending units, characterize the Bioko Squirrel Galago. Variations on this call are used for contact, spacing, cohesion, and mild alarm. Whistles and “kwoks” are also uttered.
Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. The Bioko Squirrel Galago has a relatively restricted distribution, but it does fairly well in secondary forest and remains locally common in appropriate forest habitats. It is not definitely known to occur in any officially designated protected areas, but it is found in the Southern Highlands Scientific Reserve and possibly Pico Basilé National Park, Equatorial Guinea.
Bibliography. Ambrose (1999, 2003), Bayes (1998), Bearder & Honess (1992), Butynski & Koster (1994), Charles-Dominique (1977a, 1977b), Crovella et al. (1994), de Boer (1973), Dutrillaux et al. (1982), Eisentraut (1973), Hill (1953d), Jouffroy & Gunther (1985), Masters et al. (1994), Oates (2011), Oates & Jewell (1967), Pimley (2002), Pimley et al. (2005a).
description: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Galagidae, pp. 184-209 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on pages 202-203, DOI: 10.5281/zenodo.6657019