Pteromyscus pulverulentus 131known from this host, one of which is host specifi c. A new
trypanosome, Tr y p an o s o m a k u s e li, is reported from P. volans.
Phylogeographic studies suggest that unlike many terres-
trial rodents, P. volans was forced into southern refugia dur-
ing the Pleistocene.
general references: Airapetyants and Fokin 2003; Des-
rochers et al. 2003; Hanski and Selonen 2008; Haukisalmi
and Hanski 2007; Hurme, Kurttila, et al. 2007; Hurme, Mönk-
könen, Nikula, et al. 2005; Hurme, Mönkkönen, Reunanen,
et al. 2008; Johnson-Murray 1977; Mönkkönen et al. 1997;
Oshida, Abramov, et al. 2005; Oshida, Hiraga, et al. 2000;
Painter et al. 2004; Reunanen, Mönkkönen, and Nikula
2000; Reunanen, Mönkkönen, Nikula, et al. 2004; Reunanen,
Nikula, and Mönkkönen 2002a, 2002b; Reunanen, Nikula,
Mönkkönen, et al. 2002; Sato et al. 2007; Selonen and Hanski
2003, 2004a, 2004b; Selonen et al. 2001; Shar, Lkhagvasuren,
Henttonen, et al. 2008; A. T. Smith and Xie 2008; R. W. Thor-
ington and Darrow 2000; R. W. Thorington, Darrow, and
Betts 1997.Pteromyscus Thomas, 1908
This genus contains a single species.
Pteromyscus pulverulentus
(Günther, 1873)
Smoky Flying Squirrel
description: This species is approximately twice the size
of Glaucomys sabrinus. The smoky fl ying squirrel is brown to
blackish on the dorsal surface and tail; the underparts are
white to yellowish. The face is gray.
size: Female—HB 230.8 mm; T 230.5 mm; Mass 235.0 g.
Male—HB 223.4 mm; T 222.6 mm; Mass 253.9 g.
Sex not stated—HB 250.3 mm; T 214.0 mm; Mass 268.5 g.
distribution: This species is found in southern Thailand,
peninsular Malaysia (including Penang Island), Indonesia
(Sumatra and Kalimantan), and in other parts of the island
of Borneo (Sarawak and Sabah, and Brunei Darussalam).
geographic variation: Two subspecies are recognized.
P. p. pulverulentus—Malay Peninsula and Sumatra. The up-
perparts are brownish black, with a sprinkling of white.
The underside of the patagium (“wing”) is light grayish
brown. The tail is brownish gray. The edge of the pata-
gium is yellowish white.
P. p. borneanus—island of Borneo (divided among Malaysia,
Brunei Darussalam, and Indonesia). The underparts are
a clearer whitish.
conservation: IUCN status—endangered. Population
trend—decreasing.
habitat: The smoky fl ying squirrel occurs primarily in
lowland primary forests, below 3000 m. It is a relatively rare
species that is even less common at higher elevations. Al-
though a few secure populations are found on the island of
Borneo, this species is considered endangered because of
rapid habitat loss.natural history: This nocturnal species nests in tree cavi-
ties, but it also relies on exposed nests in undisturbed forests.
It appears to be reproductive throughout the year, although
only a small number of females have been observed to be re-
productive at any one time. In western Malay sia, the average
litter size for 14 females was 1.3 (range = 1–2), with an average
pregnancy rate over a three-year period of only 9 percent.