Biology Reference
In-Depth Information
(C)
(D)
Plate 4.26
(C and D) False-water cobra (
Hydrodynastes gigas
).
Shows the groove traversing
almost the entire length of the enlarged posterior maxillary tooth.
Plate 4.26C and D, Brazilian specimens, photos copyright to David A. Warrell.
maxillary teeth of
H. gigas
as having a smooth surface. There are few additional data
regarding the specific characteristics of the maxillary dentition of the genus.
The Duvernoy's gland of
H. bicincta
(Taub, 1967)
15
had a moderately thick cap-
sule, many moderately thick trabeculae, and was composed of columnar cells (Taub,
1967). The glands were highly vascular and lumens were present in about 90% of
gland tubules. There were no mucous cells in the gland, but there was an associated
mucous supralabial gland (Taub, 1967). Fry et al. (2008) reported that the “venom
gland” (Duvernoy's gland) of
H. gigas
contained isolated mucous cells or patches and
exhibited a relatively large ovate duct. They also described a “venom vestibule” and
“venom duct” that opened to both the oral cavity and “fang sheath” (Fry et al., 2008).
4.4.3.3 Summary of the Properties and Toxinology of
H. gigas
Duvernoy's
Secretion
Glenn et al. (1992) reported a liquid yield ranging from 0 to 50 μL with a solid yield
of 1.3 mg, reportedly from a single gland. Although protein content was not reported,
these investigators noted that Duvernoy's gland of this species contained carbohy-
drate-protein complexes (Glenn et al., 1992).
Comparison of murine LD
50
and proteolytic activities of buccal salivary secre-
tions and Duvernoy's secretion highlighted the differences between these sub-
stances. The i.p. LD
50
of
H. gigas
Duvernoy's secretion was 2.0 mg/kg, while the
mixed buccal secretions s.c. LD
50
was 11.5 mg/kg, respectively (Glenn et al., 1992).
15
This is an ambiguous synonym for
H. bicinctus
, and has been used by several investigators in reference
to thus labeled, catalogued American Museum of Natural History specimens (e.g. #88401 and #60822).
Historically, major formal taxonomic descriptions beginning with Hermann (1804) have not included
“
bicincta
” as a recognized species designation for
H. bicinctus
. Due to the fluid taxonomy of non-front-
fanged colubroids, nomenclature can be complex and confusing. This again emphasizes the need for
the physician to comprehend or investigate if necessary, the biological history of any colubroid species
deemed responsible for a given snakebite presentation.
