Biology Reference
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to cause instant death (Minton, 1964). Its body fluids are equally feared as being lethal on
contact (Minton, 1964). Fear of geckos is reasonably common among some indigenous
people in Africa and Asia (Schmidt and Inger, 1966; Frembgen, 1996). In the Turkana
region of northern Kenya, bites by Ruppell's agama lizard (
Agama ruppelli orientalis
)
are feared even more than bites by
Echis pyramidum
(Geoffroy's carpet viper, Kenyan
carpet or saw-scaled viper; MacCabe, 2009; see pg. 198).
As noted elsewhere in this topic, unless the defining interpretation of the term
“venom” is modified by consensus, a rigorous body of evidence should be expected
prior to referring to any squamate oral secretion as venom. Agamids and iguanids do
not have any obvious need for the use of toxins in subjugation of their prey, and many
iguanids as well as some agamids are omnivorous with strong preferences for vegetar-
ian diet. It is interesting that aside from local perceptions in West Papua about the haz-
ards of blue-tongued skinks (
Tiliqua gigas
; see pg. 198) there are no similar reports of
such toxins or concerns about scincid lizards. The possibility of prey-specific, digestive
and/or other functions of toxins present in the oral secretions of these species requires
firm biomedical confirmation and ethological support (e.g., observations of active use in
prey capture and/or digestion). The proposed/implied clinical importance of these secre-
tions is not established or medically documented. Only in the event of well-documented
and clinically verified cases of recognizable envenomation by any of these lizards (e.g.,
varanids, agamids) can the medical risks of these species receive any due consideration.
4.5 Pitfalls Noted in Documented Cases: Differentiating
Perceived Versus Evidence-Based Risk
…
and from this, you are drawing
a conclusion?
Mishnah
Get your facts first, and then you can distort 'em as much as you please.
Mark Twain
4.5.1 Examples of Pitfalls Noted in Documented Cases
4.5.1.1 Lack of Verified Identity of Snakes Responsible for Reported Bites
Because of the uncertain medical importance of the majority of these diverse colu-
broids, identification of snakes involved in documented bites is an essential corner-
stone of risk assessment. Accounts of bites by numerous non-front-fanged colubroid
species have been negatively impacted by a lack of verified identification of the
snakes involved. Notably, the series of
70 bites attributed to
M. monspessulanus
includes probably
60 cases in which the snake was not satisfactorily identified
(
Table 4.1
; Section 4.4.2). As the victims in two of these cases had paralytic features,
accurate identification is essential and requires appropriate confirmation. Assigning
the risk of neurotoxic envenoming to a given species may equate a bite to serious
