25: Chihuahuan Nightsnake and Desert Nightsnake

I write to you from Arapahoe, Ute, and Cheyenne land. I am interested in learning about the different animals that live in the place where I was born. I want to mention that biological classification as taught by western science has its roots in racism, sexism, and transphobia – here’s a good explainer about why.

Today’s animal(s) is a funny one. We have the Desert Nightsnake (Hypsiglena chlorophaea) and the Chihuahuan Nightsnake (Hypsiglena jani) who are apparently easy enough to confuse and similar enough in form that they just count as one on CSU’s list of Colorado wildlife. As their names suggest, they are desert snakes, and are only found in the desertier portions of the state – around the Colorado River where it exits the mountains near Palisade/Grand Junction to the Utah border, in the southwest west of Durango, and around the Arkansas River in the southeastern portion of the state.

Mistaken identity is an issue for these snakes – they are also often mistaken for rattlesnakes, although they do not have the telltale rattle on their tails. They are also harmless to humans, but they do have venom which is stored in a part of their body called a Duvernoy’s gland. Neurotoxins and hemorrhagic compounds flow out of this gland and into the snake’s prey. This gland, by the way, is named for the French zoologist who first discovered it in the group of colubrid snakes in 1832. A venom gland is a pretty cool thing to have named after you – what animal body part would you want named after yourself?

These snakes also exhibit dramatic sexual dimorphism – one study found that the females could be 50% longer than the males and have triple the body mass!

Tomorrow we will talk about another harmless-to-humans animal who is often mistaken for a much deadlier one.