Colubrids, this family is not a
natural group and actually seven or more families that are
in some cases far far more closely related to elapids than
they are to other 'colubrids'.
The venoms of these snakes are in some cases just as
complex as elapids and vipers. The venoms are exactly that,
true venoms. They are not 'toxic saliva'. The gland
producing the venoms was formerly referred to as the
'Duvernoy's gland'. However, this is an artificial term that
is evolutionarily misleading, it is in fact the same venom
gland as the one found in cobras and rattlesnakes. This is
because venom evolved once, at the very base of the
Colubroidea (Advanced snakes) evolutionarily tree, long
before any of the 'colubrids' evolved. Thus, these snakes
have the same gland and produce some of the same toxins. We
even pulled out the classic cobratoxin (a 3FTx (three-finger
toxin)) from a bloody ratsnake!! The toxin was homologous to
and just as potent as a comparative cobra toxin. Same toxins
= same gland.
In the same vein, the distinction between opisthoglyphous
(rear-fanged) and aglyphous (lacking fangs) "colubrids" has
been abandoned. Not only did this distinction shoehorn a
wide variety of dentitional types into two artificial,
non-monophyletic categories, but it similarly ignored the
fact that a wide variety of "colubrids" possess complex
venoms, with widely shared toxin gene families that
transcend any divisions based on dentition
types.
email: mike at m-n-m-snakes.com (substituting the standard symbol for at)