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a large proportion of these cases. It must be pondered that in some cases the offend-
ing specimen was misidentified and actually was a viperid species. As an example,
the aforementioned case featuring cranial nerve palsies occurred in southern France.
However, in this case the victim reported having his finger deep inside the buccal cav-
ity of the snake (formally identified as a M. monspessulanus ) and thus received pro-
tracted contact with the posterior maxillary teeth (Pommier and de Haro, 2007).
Neurotoxic populations of Vipera aspis aspis (asp viper) occur in southeastern France,
and these snakes may produce the monomeric presynaptic neurotoxin, ammodytoxin B,
and/or the heterodimeric postsynaptic neurotoxin, vaspin (Guillamen et al., 2003; Jan
et al., 2002). Interestingly, neurological signs (mainly cranial nerve palsies) were
reported after bites from V. aspis in three regions of France: Languedoc-Roussillon,
Midi-Pyrénées, and Provence-Alpes-Côte d'Azur (Ferquel et al., 2007). However,
V. aspis , including specimens from South France, have quite a different appearance
than M. monspessulanus (see Plates 2.4D-F, p. 97 and 4.88A-D ), and such misidenti-
fication is unlikely. On the other hand, a person unfamiliar with M. monspessulanus or
V. aspis and experiencing anxiety after being bitten by a snake (see Section 4.5) could
conceivably affirm an incorrect identity. Also, although the wounds produced by bites
from these two species may appear different, the differences may not be distinctive.
Occasionally, bites from species such as H. nasicus or P. olfersii ( Table 4.1 and pre-
vious sections) produce local effects that resemble crotaline envenoming (see Plates
4.24D-J and 4.40A and B), while some bites from potently neurotoxic species, such
as Bungarus caeruleus (Indian blue krait; Plate 4.64 ) or some specimens of Crotalus
scutulatus [Mojave rattlesnake ( Plate 4.89A and B ); from those geographic popula-
tions that produce the PLA 2 subunit presynaptic neurotoxin, Mojave toxin, Type A
populations; Glenn et al., 1983; Weinstein et al., 1985] may produce life-threatening
envenoming without any significant local effects. Therefore, although there are data
that support concerns regarding neurotoxicity in M. monspessulanus , lack of verified
identity of the culprit snake in many cases ascribed to this species compels the need for
caution when considering the potential risks from this taxa. As noted previously, when
considering risk from possible neurotoxicity from B. irregularis , provision of an ace-
tylcholinesterase inhibitor such as neostigmine after a bite from a verified M. monspes-
sulanus could clarify the etiology of these reported effects.
4.4.2.5 Conclusion and Assessment of M. monspessulanus
The majority of reported bites from this species feature only mild local effects (many
are medically insignificant). Although neurotoxic effects are questioned in two out
of three cases because of uncertainty about the identity of the snake responsible, in
one of these cases of neurotoxicity snake identification and clinical features of cra-
nial nerve palsies were reliable. Therefore, large specimens of M. monspessulanus
should be considered potentially dangerous, and any bites from this species should
be reviewed promptly by a physician.
Assessment of Malpolon monspessulanus based on available evidence:
Hazard Level 2/3 (see Table 4.3 ).
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