Squirrels of the World

(Rick Simeone) #1
Ratufa bicolor 25

Ratufa bicolor (Sparrman, 1778)


Black Giant Squirrel


description: This is a black-and-white giant tree squirrel,
with a white or buff bib and white or buff on the side of the
face. The buff throat and cheeks are separated by a black
mustache mark. On the back the hair is black or (in some
subspecies) frosted. On the ventral surface the hair color
ranges from creamy buff to reddish yellow.


size: For most subspecies:
Female—HB 365.4 mm (n = 24); T 423.6 mm (n = 10); Mass
1236 g (n = 17).
Male—HB 335.2 mm (n = 30); T 409.3 mm (n = 50); Mass
1064.4 g (n = 31).
Sex not stated—HB 337.6 mm (n = 34); T 411.1 mm (n = 13);
Mass 1120.7 g (n = 30).
For the diminutive subspecies R. b. condorensis:
Sex not stated—HB 304.8 mm (n = 6); T 324 mm (n = 6).


distribution: This species is found through eastern Nepal
and southeast Tibet to southern Yunnan and Hainan
(China), Assam (India), Myanmar, Thailand, Laos, Cambo-
dia, and Vietnam, and south through the Malay Peninsula to
Java and Bali (Indonesia).


geographic variation: Eleven subspecies are recognized.

R. b. bicolor—Java and Bali (Indonesia). It lacks ear tufts, and
it has a fl ash pattern (i.e., an extension of the buff color-
ation of the inner surface of the forearm onto the dark
dorsal surface) on the forearms. This subspecies has
very distinctive pelage, with pale-tipped hairs on the
dorsum and completely pale hairs on the tail, making
the tail appear white. It tends to be paler on the head and
shoulders, darker on the back, and lacks a black mus-
tache line.
R. b. angusticeps—Myanmar and Thailand south through
peninsular Malaysia and the Natuna Islands (Indonesia).
It is virtually indistinguishable from R. b. leucogenys, R. b.
melanopepla, and R. b. phaeopepla. It lacks ear tufts, and it
exhibits a fl ash pattern on the forearm. Island forms on
the western sides of Myanmar, Thailand, and Malaysia
are darker black on the back and darker reddish yellow
on the belly, in contrast with the mainland forms.
R. b. condorensis—Côn Son Island (Vietnam), south of the
mainland. It is distinctive because of its small size. Oth-
erwise it is virtually identical to the mainland form, R. b.
leucogenys.
R. b. felli—small area in northern Myanmar, south and east
of the Chindwin River. It diff ers from R. b. gigantea in
lacking ear tufts, as well as in having a fl ash pattern on
the forearms. It diff ers from all neighboring subspecies
in having pale-tipped hairs on the back.
R. b. gigantea—widespread through the northern part of the
range. It is distinguished by its ear tufts and its lack of a
fl ash pattern on the forearm. On the back these animals
are more brown than black. On the venter they range
from creamy buff to yellow cream.
R. b. hainana—Hainan Island (China). This form is similar to
R. b. gigantea, but it is darker on the back, almost black in
color; it is also darker (a reddish yellow color) on the
abdomen.
R. b. leucogenys—Myanmar and Thailand south through
peninsular Malaysia and the Natuna Islands (Indonesia).
This subspecies is virtually indistinguishable from R. b.
angusticeps, R. b. melanopepla, and R. b. phaeopepla. It lacks
ear tufts, and it exhibits a fl ash pattern on the forearm.
Island forms on the western sides of Myanmar, Thai-
land, and Malaysia are darker black on the back and
darker reddish yellow on the belly, in contrast with the
mainland forms.
R. b. melanopepla—Myanmar and Thailand south through
peninsular Malaysia and the Natuna Islands (Indonesia).
It is virtually indistinguishable from R. b. angusticeps, R.
b. leucogenys, and R. b. phaeopepla. It lacks ear tufts, and it
exhibits a fl ash pattern on the forearm. Island forms on
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