176 Prosciurillus alstonihabitat: This squirrel occurs from the coastal plain to el-
evations up to 1200 m in the upper canopy of primary tropi-
cal lowland evergreen rainforests.
natural history: P. alstoni travels through the upper can-
opy via pathways formed from branches and vines. To cross
gaps in the canopy, Alston’s squirrels descend to the forest
fl oor to travel on fallen tree trunks. Their diet consists of
soft fruits and insects; fi gs were most prevalent in the stom-
ach contents. This species tends to be quiet and wary, giving
alarm calls in response to approaching rain, human noises,
and predators. Their regular calls and alarm calls are loud
strident “chatters” and “chucks,” similar to those of P. topa-
puensis. The squirrels vocalize individually, not in choruses.
A single embryo was found in each of the pregnant females.
Females have three pairs of teats: two inguinal pairs and
one postaxillary pair.
general references: Musser et al. 2010.
Prosciurillus leucomus (Müller and
Schlegel, 1844)
Whitish Dwarf Squirrel
description: The ears are bright ochraceous on the inside
and black on the outside, with a prominent black ear tuft.
This squirrel is distinguished by white or whitish buff or
grayish white patches on the nape behind the ears. The un-
derparts are reddish orange or ochraceous. The upperparts
are olive brown and may be fl ecked with orange, buff y, or
black. The tail is ringed with black and buff , terminating in
a black tuft.size: Sex not stated—HB 165–188 mm; T 140–190 mm.distribution: The whitish dwarf squirrel is found in the
northern peninsula of Sulawesi and on the neighboring is-
land of Pulau Lembeh (Indonesia).geographic variation: Two subspecies are recognized.P. l. leucomus—entire distributional range, except west of
Gorontalo on the northern peninsula of Sulawesi (Indo-
nesia). This form has prominent nape patches, and an
ochraceous muzzle and cheeks.
P. l. occidentalis—west of Gorontalo, in the middle of the north-
ern peninsula of Sulawesi (Indonesia). This form has a
pale buff or gray muzzle and cheeks. The nape patches are
diluted or even absent. The underparts are paler in color.conservation: IUCN status—data defi cient. Population
trend—no information.habitat: This squirrel can be found in coastal lowlands
and at elevations up to 1700 m in montane forests.