The Elusive Coral Snake
Easily, one of the reptiles that I am frequently asked about in the southeast, but much less frequently encounter, is the Eastern Coral Snake (Micrurus fulvius). For a snake that is seldom seen in South Carolina, I get almost as many questions about Coral Snakes as I do rattlesnakes, copperheads or cottonmouths.
First of all, as we often do, let’s take a look at that scientific name. The genus name, Micrurus, means “tiny tail”. (Micro = small, tiny or short. Oura = tail.) Snakes in this genus tend to have a rather short tail, which they often use as a distraction when they are threatened. They will lift their short tail and curl it to take attention away from their body and head.
The species name, fulvius, is derived from the Greek term to describe the color fawn, reddish, yellow (or a shade of yellow, orange). The species name was given when a faded and not-well preserved specimen was used to describe the snake. The red on the dead snake had faded to an almost orange color, instead of the vibrant reds we see on live Eastern Coral Snakes.
Next, why don’t we discuss the trick of identifying these snakes? As there are a couple of other snakes that look quite similar and have the same bright colors, combined with the toxicity of their venom, knowing how to correctly identify Eastern Coral Snakes is important. The rhyme, “Red on yellow kills a fellow. Red on black, venom lack” (or, “Red on black, friend of Jack”), is the easiest way to remember the identification of these snakes. While the Scarlet King Snake and Scarlet Snake look quite a bit like the Eastern Coral snake, their red bands and saddles touch black bands or saddles. (See this post’s photos for a better visual on the similarities and differences) Eastern Coral Snakes have banding with red touching yellow bands. This similarity is evidence of the most complex mimicry in nature. Also, Eastern Coral Snakes always have a black nose! If you look at the photos, you'll see the coral snake has a black nose; but, the Scarlet King Snake has a red nose, as does the Scarlet Snake.
Mertensian mimicry is mimicry in which the most harmful species mimics a less harmful species. This goes contrary to Batesian and Müllerian mimicry, in which less harmful, or even harmless, species mimic species that are much more harmful. (Don’t worry, we’ll discuss different types of mimicry in greater detail during a future visit with each other. I promise it’ll come back up again as we talk about insects found on the property.)
As always, if you cannot correctly identify a snake, you should always treat it as though it is venomous! That means give them respect and plenty of space.
The Eastern Coral Snake is the only venomous snake species in South Carolina that is not a pit viper. Instead, it belongs to the Elapidae family, which also includes such snakes as cobras, kraits, mambas and all Australian venomous snakes. Whereas the pit vipers have venoms made up mostly or entirely of hemotoxic proteins, which affect blood and tissue; Elapids have venoms made up mostly of neurotoxic proteins, which affect the nervous system. Their neurotoxic venom is more potent than hemotoxic venom and it takes far less of it to immobilize or dispatch prey when compared to the hemotoxic venom of pit vipers. For Eastern Coral Snakes, prey consists of other snakes, lizards and fellow reptiles.
Eastern Coral Snakes do not have the large, hinged fangs found in pit vipers. They have fixed fangs that are relatively short, often protruding only 1/8th of an inch from their upper labial scales (upper lip). Those short fangs are still very much capable of delivering enough venom to be a lethal dose, which is only about 5 milligrams for a healthy adult. Like other Elapids, Eastern Coral Snakes have proteroglyphous dentition. As we did the last time, let’s break that down to explain this scientific term. In ancient Greek, “proto” was the word for front or forward and “glypho” referred to a carved work. When the two Greek words are combined to describe dentition, it literally means, “having grooved teeth located in the front of the mouth”; which is ideal for describing fixed fangs that are located in the anterior of the mouth.
Despite what anyone may have said, humans are not too large for envenomation by Eastern Coral Snakes. They do not need to gnaw on us for an extended period of time and they do not need to bite between your fingers to cause you serious harm. Those small fangs can deliver their venom anywhere from your legs to your arms. However, Eastern Coral Snakes are the least encountered venomous snake in South Carolina and, like other snakes, they would much rather steer clear of humans. They cannot eat us; thus, they would rather not deal with us. Keeping that in mind, I was grateful to hear Sunshine say she doesn’t indiscriminately kill snakes. She doesn’t accept that whole “The only good snake is a dead snake” mumbo-jumbo. All of our native snakes, both venomous and nonvenomous, are good and they all serve a purpose.
This species should not be found in the lower piedmont area, but it is a great deal more common in Florida and the coastal plain areas of South Carolina. And I wanted to give a comparison to the far more common pit vipers to round out our lesson on the venomous snakes of South Carolina and the southeast