- There are currently 22 recognized species of venomous snakes in the United States, with a total of 37 subspecies across the country.
- All venomous snakes in the US fall into one of these four categories: rattlesnakes, copperheads, cottonmouths, and coral snakes.
- Copperheads and cottonmouths are closely related to rattlesnakes and, together, make up the pit viper family.
The United States is a massive country with a variety of habitats and environments. Within the borders of the US, there is a shocking amount of diversity among the wildlife, especially among snakes. The vast majority of snakes in the US are totally harmless to humans, but there are venomous species that live in nearly every state. Today, we are going to take a look at every single venomous snake in the United States and learn where they can potentially be found. Let’s explore a complete list of venomous snakes in the United States!
How many venomous snakes live in the United States?
While it may not seem like it, there are significantly more nonvenomous snakes in the US than there are venomous snakes. In fact, that rule holds true across most of the world, with only around 7% of all snake species being vengeful.
Still, there are quite a few venomous snake species, especially in the United States. There are currently 22 recognized species, with a total of 37 subspecies across the country. Each of these 37 subspecies can be divided into four groups of snakes. Let’s explore this further.
What are the four types of venomous snakes in the United States?
Every venomous snake in the United States fits into a small category of four groups. These four types of snakes are rattlesnakes, copperheads, cottonmouths, and coral snakes. If a snake is venomous in the United States, it is one of these four.
Rattlesnakes make up the vast majority of all venomous snakes by sheer number. The exact breakdown varies, but some sources show that there are at least 32 species of rattlesnake with over 83 recognized subspecies. Today, we will be covering the primary species of snake because many of the subspecies aren’t all that different from one another besides location or color variation.
Copperheads and cottonmouths are closely related to rattlesnakes and, together, make up the pit viper family. Pit vipers have small heat-sensing pits on their snouts that help them find prey through body heat. Copperheads and cottonmouths have subspecies within their categories, just not as many as the rattlesnake. Additionally, copperheads and cottonmouths are mostly restricted to the eastern United States.
The coral snake is a loner in the US in terms of evolutionary relationships. Coral snakes are closer to cobras and sea snakes than pit vipers and are quite rare to encounter. Still, they are venomous and considered among the most dangerous in the country.
We have broken down the venomous snakes in the United States by category below. Rattlesnake species make up the bulk of them. Additionally, the exact taxonomic breakdown of certain species is constantly being updated. The copperhead, for example, once included five subspecies but is now only broken into two groups.
Western diamondback rattlesnake
The western diamondback is one of the most common snakes in the western United States and is among the most dangerous. These snakes grow between 4-6 feet and usually come in shades of black and gray. The western diamondback is responsible for the greatest number of bites in the United States and is a contender for the highest fatality rate of any species in the country.
Eastern diamondback rattlesnake
The eastern diamondback is the largest venomous snake in the United States and is a contender for the largest in the world. Eastern diamondbacks are brown, black, and cream and can grow up to 8 feet in length. These snakes are primarily found along the coastal southeastern United States from Lousiana up into the coastal plains of North Carolina.
The timber rattlesnake is the most northerly residing venomous snake in the United States and has one of the widest ranges of any rattlesnake. Timber rattlesnakes are usually brown and gray but are known to have dark black heads and tails with occasional copper markings across their backs. They can be found through most of the southeast and midwest, with a northerly range extending well into Vermont and New Hampshire.
The sidewinder is a desert snake that gets its name from the movement it displays while moving across hot sand. Sidewinders are generally a light sandy color and grow between 1.5-3 feet, making them a bit smaller than other rattlesnake species. These snakes live in the Mojave and the Sonoran Deserts. There are three subspecies of sidewinder:
- Mojave Desert Sidewinder (Crotalus cerastes cerastes)
- Sonoran Desert Sidewinder (Crotalus cerastes cercobombus)
- Colorado Desert Sidewinder (Crotalus cerastes laterorepens)
The Mojave rattlesnake is a resident of the deep southwest, especially around the Mojave Desert. These snakes are among the most venomous in the country and are often considered to be the most venomous rattlesnakes in the world. Most Mojave rattlesnakes grow to around 3.5 feet long.
Santa Catalina rattlesnake
The Santa Catalina rattlesnake is a particular species of rattlesnake that only lives on the island of Santa Catalina, off the coast of California. These snakes don’t have rattles, and they grow to around 2 feet in length.
The rock rattlesnake is a smaller species that primarily inhabits limestone and sandstone-filled regions. Rock rattlesnakes are light-colored, often resembling the sandy stones they inhabit. There are two subspecies of rock rattlesnake:
- Banded Rock Rattlesnake (Crotalus lepidus klauberi)
- Mottled Rock Rattlesnake (Crotalus lepidus lepidus)
The speckled rattlesnake is a desert-dwelling snake that inhabits the southwest regions of the US and northern Mexico. Speckled rattlesnakes are smaller snakes, generally growing to 3.5 feet as adults. These snakes get their name from the distinct speckled pattern they often display. The subspecies of speckled rattlesnakes include:
- Southwestern Speckled Rattlesnake (Crotalus mitchelli phyrrhus)
- San Lucan Speckled Rattlesnake (Crotalus mitchelli mitchelli)
- Panamint Rattlesnake (Crotalus mitchelli stephensi)
The black-tailed rattlesnake is known as a more docile member of the entire group, with bites being quite rare. Black-tailed rattlesnakes grow between 2-3.5 feet long and are dark-colored with black tails. These snakes live in the southwestern United States.
Pacific rattlesnake (7 subspecies)
The Pacific rattlesnake is one of the most common rattlesnakes in the United States, especially with how many subspecies exist. Pacific rattlesnakes can be found across the west coast and in the desert regions of the United States. There are seven subspecies:
- Grand Canyon Rattlesnake (Crotalus oreganus abyssus)
- Coronado Island Rattlesnake (Crotalus oreganus caliginis)
- Arizona Black Rattlesnake (Crotalus oreganus cerberus)
- Yellow Rattlesnake (Crotalus oreganus concolor)
- Southern Pacific Rattlesnake (Crotalus oreganus helleri)
- Great Basin Rattlesnake (Crotalus oreganus lutosus)
- Northern Pacific Rattlesnake (Crotalus oreganus oreganus)
The twin-spotted rattlesnake is a smaller rattlesnake, rarely growing larger than two feet. Twin-spotted rattlesnakes have a distinct rounder head than most other rattlesnakes. They get their name from the two-spotted pattern that travels down their backs. These snakes live in southeastern Arizona and Mexico.
Red diamond rattlesnake
The red diamond rattlesnake gets its name from the reddish-brown coloration it is most known for. Red diamond rattlesnakes can grow as large as 5 feet long and are found in southern California and into the Baja Peninsula. Their tails are often striped black and white, giving them a quite distinctive appearance.
The tiger rattlesnake is a smaller rattlesnake with a venom that outpaces its small stature. Tiger rattlesnakes get their name from their black striping pattern that is often spread across their gray bodies. These snakes are only found across the US in central Arizona, although other populations live in Mexico.
The prairie rattlesnake is one of the most distributed rattlesnake species in the United States. Prairie rattlesnakes live across the Great Plains region of the country, from northern Mexico to the south of Canada. There are two subspecies in the US:
- Hopi Rattlesnake (Crotalus viridis nuntius)
- Prairie Rattlesnake (Crotalus viridis viridis)
The ridge-nosed rattlesnake is a smaller rattlesnake that is known for its black and white striped snout, giving it its name. Ridge-nosed rattlesnakes are quite rare snakes, only inhabiting wooded mountain ranges across Arizona and New Mexico. There are two subspecies in the US:
- New Mexican Ridge-nosed Rattlesnake (Crotalus willardi obscurus)
- Arizona Ridge-nosed Rattlesnake (Crotalus willardi willardi)
The massasauga rattlesnake is another widely distributed rattler that can be found as far south as Texas and as far north as Canada. The three different subspecies are found across distinct ranges, with the eastern massasauga being the most northerly and widespread. The three subspecies are:
- Eastern Massasauga (Sistrurus catenatus catenatus)
- Desert Massasauga (Sistrurus catenatus edwardsii)
- Western Massasauga (Sistrurus catenatus tergeminus)
Pygmy rattlesnake (3 subspecies)
The pygmy (sometimes spelled pigmy) rattlesnake is the smallest species of rattlesnake in the United States. Pygmy rattlesnakes are primarily found in the southeastern United States around coastal plains regions. Their small size and low-potency venom make them among the least dangerous species of rattlesnake around. There are three subspecies of pygmy rattlesnake in the US:
- Dusky Pygmy Rattlesnake (Sistrurus miliarius barbouri)
- Carolina Pygmy Rattlesnake (Sistrurus miliarius miliarius)
- Western Pygmy Rattlesnake (Sistrurus miliarius streckeri)
Cottonmouths are large aquatic snakes that are quite venomous. These members of the pit viper family are known for their bright white mouths that they flash as a warning to potential predators. The cottonmouth is native to the southeastern United States and has three subspecies. Unlike rattlesnakes, however, these subspecies are more similar to one another and are still grouped under a single species.
Cottonmouths are usually considered to be less venomous than most species of rattlesnake, although they are more dangerous than copperheads. As aquatic snakes, they are most often found in swampy lowland regions near or in water. Rivers, streams, swamps, and wetlands are the primary habitats for these vipers.
There are three subspecies of cottonmouth spread across the southeast:
- Florida Cottonmouth (Agkistrodon piscivorous conanti)
- Western Cottonmouth (Agkistrodon piscivorous leucostoma)
- Eastern Cottonmouth (Agkistrodon piscivorous piscivorous)
Copperheads are the most commonly encountered venomous snakes in the southeastern United States. They get their name from their distinct copper-colored bodies and brown hourglass patterns across their backs. Other features include golden cat-like slitted eyes, distinct pits around the snout, and a triangular head.
Because copperheads rely on camouflage as their primary method of defense, they are often unseen and accidentally stepped on or touched. As a result, they make up the majority of bites in many states across the southeast. They generally prefer wooded and forested areas where they can blend into the underground and brush.
Thankfully, copperheads are the least venomous of all pit vipers, and bites are rarely fatal.
Historically, copperheads were divided into five subspecies, but recent taxonomic groupings have reduced those five into two groups. The historic groups are still used, however, and include:
- Northern Copperhead (Agkistrodon contortrix mokasen)
- Southern Copperhead (Agkistrodon contortrix contortrix)
- Broad Banded Copperhead (Agkistrodon contortrix laticinctus)
- Trans-Pecos Copperhead (Agkistrodon contortrix pictigaster)
- Osage Copperhead (Agkistrodon contortrix phaeogaster)
Today, the northern, southern, and Osage copperhead subspecies are considered eastern copperheads. Broad-banded and Trans-Pecos copperheads are now considered broad-banded copperheads.
Coral snakes are different from all other venomous snakes in the United States as they are Elapids, meaning they are closer to cobras and sea snakes than pit vipers. There are close to 50 species of coral snake in the Americas, but there are only three species that live in North America. Coral snakes are brightly colored and have banding patterns of black, red, and yellow.
These snakes are highly venomous and have a primarily neurotoxic venom when compared to pit vipers. Despite having highly toxic venom, coral snakes have a poor venom delivery system. Additionally, they are extremely rare and spend most of their time under brush and logs.
There are three species of coral snake in the United States:
- Arizona coral snake (Micruroides euryxanthus)
- Eastern coral snake (Micrurus tener)
- Texas coral snake (Micrurus fulvius)
Summary of Venomous Snakes in the United States
|1||Western Diamondback Rattlesnake|
|2||Eastern Diamondback Rattlesnake|
|4||Mojave Desert Sidewinder|
|5||Sonoran Desert Sidewinder|
|6||Colorado Desert Sidewinder|
|8||Santa Catalina Rattlesnake|
|9||Banded Rock Rattlesnake|
|10||Mottled Rock Rattlesnake|
|11||Southwestern Speckled Rattlesnake|
|12||San Lucan Speckled Rattlesnake|
|15||Grand Canyon Rattlesnake|
|16||Coronado Island Rattlesnake|
|17||Arizona Black Rattlesnake|
|19||Southern Pacific Rattlesnake|
|20||Great Basin Rattlesnake|
|21||Northern Pacific Rattlesnake|
|23||Red Diamond Rattlesnake|
|27||New Mexican Ridge-nosed Rattlesnake|
|28||Arizona Ridge-nosed Rattlesnake|
|32||Dusky Pygmy Rattlesnake|
|33||Carolina Pygmy Rattlesnake|
|34||Western Pygmy Rattlesnake|
|40||Broad Banded Copperhead|
|43||Arizona Coral Snake|
|44||Eastern Coral Snake|
|45||Texas Coral Snake|
Discover the "Monster" Snake 5X Bigger than an Anaconda
Every day A-Z Animals sends out some of the most incredible facts in the world from our free newsletter. Want to discover the 10 most beautiful snakes in the world, a "snake island" where you're never more than 3 feet from danger, or a "monster" snake 5X larger than an anaconda? Then sign up right now and you'll start receiving our daily newsletter absolutely free.
More from A-Z Animals
The Featured Image
Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.