Biology Reference
In-Depth Information
pain, and edema etc.; see the seven species listed in
Table 4.1
, and there are also addi-
tional insignificant anecdotally reported bites by Forsten's cat snake,
B. forsteni
(Plate
4.8;
Table 4.1
), as well as the many-spotted or marble cat snake,
B. multimaculata
].
Most
Boiga
spp. attain an average adult length of 1.0-2.0 m, although some taxa (e.g.,
Blanding's tree snake,
B. blandingi
and the brown tree snake,
B. irregularis
) may exceed
3.5 m (Pitman, 1974; Fritts and McCoid, 1999; SAW personal observations).
Boiga
(
Toxicodryas
Trape and Mané 2006)
blandingi
(Plate 4.5A and B) is subjec-
tively viewed with suspicion by some authors (Groves, 1973; Levinson et al., 1976;
Spawls, 1979; Goodman, 1985), although the few documented bites have featured
only minor puncture wounds/lacerations, mild local pain, and slight bleeding (
Table
4.1
). Notably, around its range in the Kakamega Forest in western Kenya, this snake is
feared by some of the local Luo people. The less spectacular, closely related, and sym-
patric
B.
(
Toxicodryas
LeGrand, 2002)
pulverulenta
(powdered or blotched tree snake)
is not similarly perceived. Possibly, the large adult size and gaping mouth defensive
display of
B. blandingi
(Plate 4.5B) adds to its somewhat fearsome reputation.
Despite several cases posted on the Internet that illustrate severe local swelling,
bruising, and hemorrhagic blister formation following purported
B. dendrophila
bites (see Appendix A), the two published cases and several others from anecdotal
accounts developed only mild symptoms (
Table 4.1
). This is concordant with the
experiences of one of the authors (SAW), who received several insignificant bites
(mild pain and brief bleeding) from
B. d. melanota
and
B. d. multicincta
. Although
some observers have voiced concerns about the possible life-threatening risks of spe-
cies such as
B. forsteni
in Sri Lanka, at this time there are no documented cases or
other evidence that support these perceptions (De Silva, 1976a; Fritts and McCoid,
1999; Fritts et al., 1994). As noted earlier, the distinctive circumstances surrounding
risks from
B. irregularis
are discussed in Section 4.4.
4.2.1.1 Overview of the Duvernoy's Gland and Associated Dentition
of
Boiga
spp.
Although the presence of grooved, enlarged maxillary teeth is generally established for
members of the genus, there are few data regarding the specific characteristics of the
maxillary teeth present in various
Boiga
spp. Taylor (1922) reported that
Boiga
spp.
found in the Philippines (including
B. dendrophila
) possessed “two or three” grooved
posterior maxillary teeth. Fry et al. (2008) reported that
B. irregularis
had enlarged
posterior maxillary teeth with deep grooves running their entire length.
Plates 4.7C and
D and 4.9E and F
respectively show the enlarged, deeply grooved posterior maxillary
teeth of
B. dendrophila
and
B. irregularis
. The teeth are gently recurved, notably larger
than the preceding dentition, and the grooves span almost the entire length of the teeth.
In an extensive comparative histological study of colubrid oral glands, Taub
(1967) assessed the morphology of Duvernoy's glands from several
Boiga
spp. He
described the glands of
B. dendrophila
,
B. d. latifasciata
, and
B. blandingi
as having:
capsules with “heavy” to “very heavy” thickness (that of
B. dendrophila
was slightly
thicker than that of
B. blandingi
or
B. d. latifasciata
); noted vascularity; and numer-
ous thin (
B. d. latifasciata
) or “heavily thick” trabeculae. The glands lacked mucous
