As a part of the A-Z Photographic Glossary of Biological Terms challenge, today it is O for Opisthoglyphous, as illustrated by this pair of Small-spotted Cat-eye Snakes (Leptodeira septentrionali polysticta; Colubridae) from the Sittee River Wildlife Reserve in Stann Creek District, Belize.
The common name, Cat-eye, comes from this beautiful snake’s vertical pupils. It is a semi-arboreal species and a mildly venomous hunter of frogs and toads and their eggs and tadpoles. Bearing in mind that all snakes, in fact all wild animals, should only be handled in very specific circumstances and only by someone with the proper experience and expertise, this is a very calm and docile animal when being handled.
It poses very little threat to humans because unlike the venomous elapids (including coral snakes) with forward-grooved fangs (proteroglyphous) and the venomous vipers (lanceheads like the Fer-de-Lance, rattlesnakes, bushmasters, and pit vipers) with pipe-grooved fangs (solenoglyphous), this species is what is known as “opisthoglyphous” or rearward-grooved.
In opisthoglyphous snakes, their venom is injected by a pair of enlarged teeth at the back of the jaws which normally angle backwards and are grooved to channel venom into the puncture. Since these fangs are not located at the front of the mouth this arrangement is vernacularly called “rear-fanged”. In order to envenomate prey, an opisthoglyphous snake must move the prey into the rear of its mouth and then penetrate it with its fangs, presenting difficulties with large prey, although they can quickly move smaller prey into position.