Medically Significant Bites by “Colubrid” Snakes - "Venomous" Bites from Non-Venomous Snakes - page 169

4.2.5.3 Conclusion and Assessment of Hemorrhois spp., Platyceps spp.,
Hierophis spp., and Coluber spp.
Little information is available about properties of Duvernoy's secretions from these
taxa, and the few documented bites have featured only mild effects. Two aberrant cases
involving Hierophis viridiflavus and P. najadum reported in the literature were serious
or fatal, but these consequences are most unlikely to have been related to “envenom-
ation” by either of these snakes, and identification of the snake responsible is ques-
tionable in at least one of these cases (see Section 4.4). Therefore, available evidence
supports only mild, local effects resulting from bites by these taxa. Large specimens of
P. najadum and P. rhodorachis might produce more significant local pathology.
Assessment of Coluber spp., Hemorrhois spp., Hierophis viridiflavus ,
Platyceps spp. based on available evidence: Hazard Level 3/4 (see Table 4.3 ).
4.2.6 Genus Alsophis spp.: Background and General Features of
Documented Bites
The genus Alsophis (West Indian, Caribbean or Central American, South American,
and Galapagos racers) belongs to the family Dipsadidae, subfamily Xenodontinae,
tribe Alsophiini, and contains approximately 14 species. Some taxa have multiple
subspecies with the Cuban racer or jubo, A. cantherigerus , probably having largest
number of subspecies (approximately eight). Most taxonomic studies have supported
monophyly of the West Indian species (Hass et al., 2001; Vidal et al., 2000; Zaher,
1999) that are probably derived from a South American stock origin. This group has
also been subjected to ongoing systematics investigations, and the tribe Alsophiini
has recently been reorganized with reclassification of the alsophiines into 10 genera
(seven previously named, and three new; Hedges et al., 2009). This included recom-
mendation for reassignment of A. portoricensis (Puerto Rican racer; culebra corredora
puertorriqueña; Plate 4.2A-F) and A. cantherigerus to the new genera, Borikenophis
and Cubophis , respectively (Hedges et al., 2009). This is especially relevant due to the
occasional reports of medically significant bites by these species ( Table 4.1 ). For pur-
poses of the present discussion, the previous taxonomic designations will be used as, to
date, these terms are used exclusively in the body of limited literature about bites by these
snakes. Most Alsophis spp. attain an average total body length of about 0.8-1 m (although
some specimens may be significantly longer), are fast moving, and are found in a diverse
range of tropical habitats including sparsely vegetated scrub, arid sandy coastal tus-
sock, moist meadow/grasslands, cultivated fields, and rainforest as well as rocky ter-
rain. Although most species feed on a wide range of prey, including small mammals,
and occasionally bats or nestling birds, many species exhibit preference for amphibians
[especially hylid frogs (treefrogs such as Osteopilus spp.)], lizards (e.g., anoles, Anolis
spp., gekkonids, and other taxa), and other snakes [e.g., Tropidophis spp. (dwarf boas or
wood snakes; family Tropidophidae)]. Schwartz and Henderson (1991) reported that gek-
konids [e.g., Sphaerodactylus (reef or dwarf geckos)] and the hylids, peeping, chirping,
or robber rainfrogs ( Eleutherodactylus spp.) comprised a large proportion of the diet of
A. cantherigerus . Alsophis spp. (e.g., Plate 4.3A-E) are active diurnal foragers that will