Biology Reference
In-Depth Information
(H)
(I)
(J)
(K)
Plate 4.56
(H-K) Maxilla and enlarged posterior maxillary teeth of
T. kirtlandii
.
Note the
multiple enlarged, deeply grooved posterior maxillary teeth (arrows). Chameleons (
Chameleo
spp.) are favored prey, and these lizards succumb rapidly when grasped by a
T. kirtlandii
.
Plate 4.56
H-K, AMNH #75091, photos copyright to Scott A. Weinstein.
spp. and
D. typus
retain this prominent ridge on the anterior surface of the teeth,
and the ridge arises within the groove in
Thelotornis
spp., thus dividing the “venom
canal” (
groove) (Broadley and Wallach, 2002). The division formed by this modi-
fication terminates well before the tip of the respective posterior maxillary teeth
(Broadley and Wallach, 2002). This is particularly significant, as Broadley (1968)
noted that
D. typus
can strike with the enlarged maxillary teeth in a forward orienta-
tion thereby increasing contact with the intended target. The jaw kinetics of this spe-
cies probably adds an additional dimension to this capability, as these snakes exhibit
a wide gaping capacity (to about 170°; Marais, 1985) that increases the likelihood of
greater biting contact and bitten surface area. However, with the posterior venom-
delivery apparatus, some bites will fail to result in envenoming. Cooper and Reid
(1976) discussed several asymptomatic and insignificant
D. typus
bites reported by
Ionides. Therefore, although rapid envenoming (i.e., strike and release) by “opistho-
glyphous” and “aglyphous” snakes certainly occur (Warrell, 2004), “dry” bites are
likely common, as they are with some viperids.
Little information is available about the specific dentitional characteristics of
Thrasops
and
Rhamnophis
. The three posteriormost maxillary teeth of
T. flavigularis
