Some Seemingly Harmless Snakes Possess a Secret Venom Gland

Usually, we think of snakes as falling into one of two groups—venomous and nonvenomous. But to the surprise of herpetologists, a new group has emerged, which seems to fall into a previously unknown grey area between venomous and not.

This discovery occurred after victims who received bites from “harmless” snakes—Thrasops flavigularis in Africa and green whip snakes in Europe—began showing suspect symptoms, including problems with neuromotor skills. Upon closer examination, herpetologists noticed that both of those culprit species possess something called the Duvernoy’s gland. Researchers have long puzzled over what this gland’s purpose is; some think it’s used for helping the snakes swallow and digest food, while others believe it’s a primitive version of what scientists consider true venom glands. With these latest findings, however, herpetologists writing in the journal Toxin propose classifying it as a true venom gland.

Don’t mess with the green whip snake. Photo: Jean-Jacques Milan

Before nonvenomous snakes become even more loathed than they largely already are, however, it’s important to note two points the researchers make about these extremely rare events. In all cases of these species causing harm, people were either handling or attempting to capture the animal. Secondly, all of those bites went on for quite a while—one to five minutes. The researchers don’t explain why someone would allow a snake to continue biting them for five full minutes (“for various reasons,” they mysteriously write), but it’s probably safe to assume most victims were not acting in the smartest way—and certainly not how most of us act around snakes, venomous or no.

More from Smithsonian.com:

Five Giant Snakes We Should Worry About
When Tentacled Snakes Attack 

Rachel Nuwer | | READ MORE

Rachel Nuwer is a freelance science writer based in Brooklyn.