A quick guide to North American snakes

Well, I suppose I need some more science-y material, so what better thing to cover than North American snake identification? (HT: Stacy S. for the idea) I’ll be going in-depth with each family of snakes, but for now, we’ll start with some basics!

Common families: Colubridae, Elapidae, Viperidae
Uncommon families: Loxocemidae, Anomalepididae, Leptotyphlopidae, Boidae, Tropidophiidae

We’ll start with the common ones so you can quickly narrow down what a specific animal is NOT (below the fold).

Elapids:

Native Elapid snakes present in the Americas are restricted to the so-called “coral snakes.” I put this in quotations because how we define this group is rather ambiguous. Of these, there are many species, but I’ll only focus on the prominent North American version. Micrurus is the only genus found in the United States. As far as I know, most of the North American species of “coral snakes” have the tell-tale black-yellow-red markings in TYPICAL individuals. I cannot stress enough that coloration can vary in any species of snake. I’m going to give you some additional tools other than how to identify the typical coloration of snakes. These will be morphological characteristics to help you identify them. What makes a Micrurus snake:
1) Short, blunt, rounded head
2) Head not much larger in diameter than the neck, although easily noticeable

All coral snakes will be thin bodied and usually less than 3′ in length. If you have a snake over 5′ in length, it is definitely not a coral.

North American vipers:

These can be broken down into two easily distinguishable groups: pit vipers and pit vipers (intentional). One group of pit vipers in North America are often called “rattlesnakes” while another group are called “cottonmouths” and “copperheads.” The differences within the rattlesnakes are actually far more pronounced than the differences between the Agkistrodon species (Copperheads and cottonmouths). Here is a really easy way to identify vipers in North America:

The neck will be much more narrow than the base of the head; If rattles are present, it is definitely a rattlesnake, however, some other species are known to beat their tails into the underbrush resulting in a rattle-like sound. Look for the actual rattle or an ossified tail tip; pit vipers almost always have eyes which are partially or completely concealed when looking at the snake dorsally. If you can clearly see both eyes completely from the dorsal angle, no rattles are present, and the neck is not highly constricted, you can be fairly certain it is not a dangerous species, excluding the Micrurus variety.

Colubrids

I cannot possibly get into an accurate description of all North American Colubrids here, so we’ll do like the taxonomists did for a few hundred years and use this as our lump category for all snakes that don’t fit into either of the other two categories which are present in the United States. Chances are, you’re right. Loxocemidae is present only in Mexico on southwards. Anomalepididae are found in similar distributions. Leptotyphlopidae are very small snakes called “threadsnakes” which look more like earthworms than snakes. Boidae also is located outside of the United States, as are Tropidophiidae. Pythons are also present in the United States (in Florida) due to the release of “pet” reticulated pythons.

The lesson here is to leave it alone if it:

1) has dorsally obstructed eyes
or
2) has a rattle
or
3) has hallmark black-yellow-red-yellow-black-yellow-red-yellow-black… markings on the body