Red-necked Keelback

Rhabdophis subminiatus is a rear-fanged species and was previously thought to be harmless. However, following one fatal and several near-fatal envenomations, the toxicity of its venom was investigated. As a result, it has recently been reclassified as a dangerous species. In general, rear-fanged snakes need to bite and hold on, or repeatedly bite, to have any effect on humans. But recently, there have been reports of cases where even brief bites have resulted in severe envenomation and organ failure, affecting the kidneys and liver. A chewing action facilitates envenomation, as the venom ducts open to fangs that are externally grooved (not hollow) and are posterior in the oral cavity. R. subminiatus has enlarged and ungrooved teeth. The species has two enlarged teeth in the back of the jaw. Located in the upper jaw is a gland known as Duvernoy's gland, which produces an extremely venomous secretion.

Symptoms caused by venom and poison. When the snake bites, the salivary venom mixture is not injected, but it flows into the punctures produced by the upper jaw's rear teeth, which can penetrate the skin of humans. The venom from R. subminiatus has been responsible for internal hemorrhaging, including hemorrhaging of the brain, as well as nausea, coagulopathy, and even disseminated intravascular coagulation. Also, when the venom was tested on animals, kidney failure was reported. …