Squirrels of the World

Prosciurillus alstoni 175

Prosciurillus abstrusus Moore, 1958

Secretive Dwarf Squirrel

description: This species is one of the smaller squirrels
endemic to Sulawesi (Indonesia). The secretive dwarf squir-
rel’s upperparts, tail, and head are dark brown fl ecked with
pale buff. The underparts are dark grayish white; on some
specimens, there is a pale buff wash on the chest region. The
ears are conspicuously white on the dorsal surface. P. abstru-
sus is similar in size and coloration to P. murinus, but the
coloration of P. abstrusus is duller, and the ears of P. murinus
lack the white coloring on those of P. abstrusus.

size: Sex not stated—HB 115–148 mm; T 72–130 mm.

distribution: This squirrel is known only from the type
locality: on the Pegunungan (= mountain range) Mekongga
in southeastern Sulawesi (Indonesia).

geographic variation: None. However, the information

is insuffi cient.

conservation: IUCN status—data defi cient. Population

trend—no information.

habitat: P. abstrusus is found at elevations between 1500

and 2000 m, where the habitat is transitional from lower to

upper tropical montane forests.

natural history: Little is known about the secretive

dwarf squirrel. Females have three pairs of teats: two ingui-

nal pairs and one postaxillary pair.

general references: Musser et al. 2010.

Prosciurillus alstoni (Anderson, 1879)

Alston’s Squirrel

description: The upperparts are dark brown with high-

lights of buff , orange, or black. The underparts are dark red to

reddish brown. Most of these squirrels have white fur on the

external parts of the ears, with prominent white ear tufts.

The tail is patterned by alternating rings of black and buff.

size: Sex not stated—HB 157–195 mm; T 135–180 mm; Mass

135–210 g.

distribution: On Sulawesi (Indonesia), it is found on the

eastern central peninsula, the eastern part of the central

core, and the southeastern peninsula. It also inhabits the

outlying Indonesian islands of Pulau Buton and Pulau

Kabaena.

geographic variation: None.

conservation: IUCN status—no information. Population

trend—no information.

Prosciurillus Ellerman, 1947

The genus Prosciurillus contains seven species that are en-
demic to the island of Sulawesi and to the smaller surround-
ing islands in Indonesia. J. R. Ellerman fi rst proposed the
new genus Prosciurillus for Sciurus murinus, after noticing
that the Sulawesi dwarf squirrels and others in the Indoma-
layan region had a relatively short orbit. He compared Pro-
sciurillus to the South American pygmy squirrel genus Sciu-

rillus, even though the two groups are not phylogenetically

close. Not much is known about Prosciurillus. The most cur-

rent information available comes from G. Musser’s recent

publication on the Sulawesi squirrels and their associated

sucking lice. More fi eldwork on the natural history of the

squirrels in this region of the world is needed.