Biology Reference
In-Depth Information
Assessment of
B. irregularis
based on available evidence: Hazard Level 2/3
(see
Table 4.3
).
4.4.2
Malpolon monspessulanus
4.4.2.1 Background and Aberrant Features of Bites
The genus
Malpolon
(malpolon, hooded snakes) consists of two species,
M. mon-
spessulanus
(Montpellier or yaleh snake; Plate 2.4D-F, p. 97) and
M.
(
Scutophis
Padial, 2006)
moilensis
(Moila's or hooded snake; Plate 4.33A and B).
Malpolon
monspessulanus
(two subspecies,
M. m. monspessulanus
and
M. m. insignitus
;
both are known as western Montpellier snakes) has purportedly been involved
in
70 documented bites, the majority of which resulted in uncomplicated local
wounds (puncture wounds/lacerations, mild edema, etc.; Plate 2.4G, p. 97;
Table
4.1
). Boulenger (1913) commented that
Malpolon
“poison” (secretion) had
action “similar” to that of cobras. Three published cases have described systemic
effects including ptosis and other cranial nerve palsies; peripheral neurotoxicity;
and “drowsiness” (
Table 4.1
). It is important to emphasize that the identity of the
snake responsible was unverified in many of the previous cases assigned to
M.
monspessulanus
.
There is only one documented bite from the congener,
M. moilensis
, and that bite
resulted in insignificant effects (
Table 4.1
).
4.4.2.2 Overview of the Duvernoy's Gland and Associated Dentition of
M. monspessulanus
Boulenger (1913) reported that
M.
(
Coelopeltis
)
monspessulanus
have “maxillary
teeth that are small and subequal, followed after a short interspace by one or two very
large grooved fangs situated below the posterior border of the eye.” Fry et al. (2008)
noted that some of the posterior teeth of
M. monspessulanus
possessed a deep groove
that ran most of their length. These authors also interpreted buccal mucosa associated
with these teeth as a “fang sheath” (Fry et al., 2008). Examination of several living
M. monspessulanus
and osteological specimens show the notably enlarged, deeply
grooved, recurved posterior maxillary teeth (Plate 2.4A-C, p. 13).
Taub (1967) described the Duvernoy's gland of
M. monspessulanus
as having a
thick capsule and few thin trabeculae. The gland was composed of columnar cells, and
about 10% of the tubular constituents had a lumen. The gland exhibited moderate vas-
cularity and lacked mucous cells (Taub, 1967). However, Fry et al. (2008) reported that
the
M. monspessulanus
“venom gland” (Duvernoy's gland) contained isolated mucoid
cells or patches and a relatively large ovoid duct. They also described the presence of
a “venom vestibule,” defined as “a localized expansion of the venom duct,” adjacent to
the gland (Fry et al., 2008). The “venom duct” opened into both the oral cavity and the
“fang sheath” (Fry et al., 2008).
