Squirrels of the World

Prosciurillus weberi 179

tions, and it is doubtful if the current range of P. rosenbergii
is as extensive as it was when recorded in the late 1800s.

geographic variation: None.

conservation: IUCN status—least concern. Population
trend—stable.

habitat: There is no information on P. rosenbergii, but con-
sidering that it is similar in morphology to P. alstoni and P.
topapuensis, P. rosenbergii is suspected to dwell in the upper
canopy.

natural history: No information is available.

general references: Musser et al. 2010; Riley 2002.

Prosciurillus topapuensis (Roux, 1910)

Mount Topapu Squirrel

description: This squirrel has black ear tufts that range
from prominent to faint. The upperparts are brown with
buff or black highlights. The underparts are dark gray
washed lightly with pale buff or ochraceous, and some are
tinted with silver. P. topapuensis lacks the mid-dorsal stripe
and nape patches seen in other squirrels of similar coloring.
It has a buff y ring around each eye, and a buff y-colored
muzzle. The tail, which is shorter than the length of the

head and body, is colored with rings of black and buff , with

short buff y and black bands outlining the margins of the

tail. The tail ends in a black terminal tuft.

size: Sex not stated—HB 155–190 mm; T 120–175 mm; Mass

130–210 g.

distribution: P. topapuensis can be found in the mountains

in the western section of the central core island of Sulawesi

(Indonesia).

geographic variation: None.

conservation: IUCN status—no information. Population

trend—no information.

habitat: This squirrel is found at elevations from 350 to

2800 m, in habitats ranging from tropical lowland evergreen

rainforests in the foothills to montane rainforest forma-

tions.

natural history: P. topapuensis inhabits the upper can-

opy of primary forests, staying mostly in the tree crowns

and on woody vines. When on the ground, these squirrels

utilize living and dead vines and tree branches and trunks

to transverse the ground and cross streams. They are diur-

nal, active mostly in the mornings and afternoons on sunny

days, but they may be active all day during overcast weather.

They are thought to place their leaf nests in tree cavities,

especially those of strangler fi gs (Ficus aurea). Their stomach

contents indicate that they have a diet of soft fruits, some

seeds, and arboreal insects. Figs were prevalent in the stom-

ach contents. This species’ behavior ranges from wary and

quiet to loud and aggressive. Their vocalizations are “chat-

ters”: loud, resonant, and scolding. The squirrels are sensi-

tive to human voices and presence, the sounds of trees and

limbs falling, approaching rain, and aerial predators; they

will vocalize at all of these noises. The squirrels tend to call

individually, not in a chorus. Females have three pairs of

teats: two inguinal pairs and one postaxillary pair.

general references: Musser et al. 2010.

Prosciurillus weberi (Jentink, 1890)

Weber’s Dwarf Squirrel

description: Weber’s dwarf squirrel is distinguished by

its prominent black ear tufts and by the broad black mid-

dorsal stripe extending from the neck to the base of the tail.