Biology Reference
In-Depth Information
(B)
(C)
Plate 4.59
(
Continued
)
(C) False-Fer-de-Lance; Cuaima Sapa (
Xenodon severus
), Porto
Velho, Brazil (found dead on road).
There is an obscure anecdotal report that allegedly
reports a
X. severus
bite with a fatal outcome. This report has not yet been reviewed, and there
is no available evidence that supports any significant hazard associated with this species. The
single documented case consisted of only mild local effects (see Section 4.3 and
Table 4.1
).
Plate 4.59A-C, photos copyright to David A. Warrell.
Many of these minor cases received combined evidence rankings between levels C
and D due to: very limited documented reports (frequently only single reports); nume-
rous accounts authored by medically unqualified observers; limited information in
the report, or secondhand accounts; the very mild effects of bites inflicted by the spe-
cies involved, as well as the possible influence on signs and symptoms of first-aid treat-
ments, and acquired hypersensitivity to venom or other ophidian products (salivary
proteins, shed skins, etc.). Bites from many of these species (e.g., the garter and ribbon
snakes,
Thamnophis
spp., and the Asian racers,
Hemorrhois
spp.) produce mild local
reactions typically featuring erythema, puncture wounds/lacerations, mild pain, and,
occasionally, ecchymoses, lymphadenitis/lymphangitis (Hayes and Hayes, 1985), and
hemorrhagic vesicles (Gomez et al., 1994;
Table 4.1
). Some of these accounts suggest
significant distress and anxiety due to the unexpected nature of
any
uncomfortable effects
from what was perceived as a “harmless” or “nonvenomous” species.