40 Snakes in Illinois (Pictures and Identification)

Illinois is home to a wide number of snakes. Most of these snakes aren’t venomous. Others are mistakenly associated with venomous snakes.

Many describe venomous and non-venomous snakes in Illinois as Water moccasins. But only 4 species of snakes in the state are truly venomous.

Are There Venomous Snakes in Illinois?

Many rattling tail snakes in Illinois are seen as venomous. However, there are only a handful of venomous snakes in the state.

Venomous snakes use their venom every time they bite or on occasional bites when they need to overpower prey such as birds or mammals.

Massasauga, Cottonmouth, Timber rattlesnake, and the Copperhead snakes are the only 4 venomous species that live in Illinois. Many other species are found in the state.

40 Types of Snakes in Illinois

1. Copperhead

Copperhead

Scientific name: Agkistrodon contortrix

Common name: eastern copperhead, copperhead

Venomous: Yes

Copperheads are a common species of venomous snakes. While not lethal and not as powerful as the venom of Cottonmouth snakes, the venom of Copperheads still requires medical attention.

These snakes are known to use a small amount of venom in initial or first bites. They only insert a small amount of venom which means bitten people survive a Copperhead attack.

While this small amount of venom isn’t fatal it still comes with extreme pain. Shivering, swelling, and even suffering from extreme nausea have been reported following Copperhead bites.

These species aren’t easy to see in Illinois during the summer days as they’re nocturnal on the warm days. They turn diurnal in cooler weather specific to the spring and fall months.

2. Cottonmouth

Cottonmouth

Scientific name: Agkistrodon piscivorus

Common name: cottonmouth, water moccasin, swamp moccasin, black moccasin, viper

Venomous: Yes

Cottonmouth snakes are more venomous than Copperheads. While reported death cases following Cottonmouth bites are rare, reactions to its venom are severe.

Amputation might be required in extreme cases where antivenom is delayed.

These highly venomous snakes are identified by their size and coloring. They grow up to 31 inches and they are mostly seen in an almost all-black coloring.

Cottonmouths can be found in areas with bodies of water across the state. While they are adapted to aquatic environments they might also be seen in other habitats.

These snakes are known to eat a wide range of prey which includes turtles, birds, and fish.

3. Timber Rattlesnake

Timber Rattlesnake

Scientific name: Crotalus horridus

Common name: timber rattlesnake, canebrake rattlesnake, banded rattlesnake

Venomous: Yes

The Timber Rattlesnake is a venomous species that are found across the US, including Illinois. The species is considered one of the truly dangerous snakes through its long fangs that easily pierce human and animal skin.

People can read its warning signs for defense as Timber Rattlesnakes rarely attack directly. They rattle their tails first.

This species is can be seen in forests around the state. Pregnant females can be seen in the summer as they prefer to exit forests and head towards open warmer areas.

4. Massasauga

Massasauga

Scientific name: Sistrurus catenatus

Common name: massasauga, massasauga rattlesnake, massasauga rattler (Ontario), black massasauga, black rattler, black snapper.

Venomous: Yes

This species is a known pit viper snake. Massasauga snakes are known to be venomous.

Snakes of the species are predators known to kill small animals. Their venom is known to disturb the blood system of animals which inhibits blood clotting.

Snakes of the genus have heat-sensing pits next to the eyes which helps them quickly discover warm-blooded animals.

These snakes are identified by a patterned color with gray and brown coloring.

Massasauga snakes grow to a maximum size of around 31 inches. While highly venomous, they rarely bite people.

Most bites happen when people accidentally step on this snake, such as when hiking.

5. Smooth Earth Snake

Smooth Earth Snake

Scientific name: Virginia valeriae

Common name: smooth earth snake

Venomous: No

The Smooth Earth Snake is common in the Eastern parts of the US. Part of the Colubridae snake family, it’s one of the fossorial species in Illinois.

Snakes of this genus spend most of their time underground. Its behavior is highly influenced by its diet.

Smooth Earth Snakes eat earthworms.

Known for its uniform dark body, this snake is also known for its reduced size. It grows to a maximum length of 9.8 inches in adulthood.

Common in urban environments, the Smooth Earth Snake might come out of the ground after the rain. It generally runs when it sees people. It might also defecate to keep potential predators away.

6. Midwestern Worm Snake

Midwestern Worm Snake

Scientific name: Carphophis amoenus helenae

Common name: Central twig snake, central worm snake, ground snake, Helen’s snake, Helen Tennison’s snake, Helen’s worm snake, red snake, worm snake, Midwestern worm snake

Venomous: No

This Midwestern Worm Snake is the most common species in Illinois. This short snake is common in forests, particularly on rocky terrains.

A small species in the Midwest, the snake is known to grow to a maximum length of 9.8 inches as an adult.

It’s identified by a dark brown back color and a pink belly color.

This small snake is known to live a long life. It mates at the end of the fall but it only lays eggs the following year at the beginning of the summer.

Females of the species lay a cluster of 2 to 5 eggs.

7. Western Worm Snake

Western Worm Snake

Scientific name: Carphophis vermis

Common name: Western worm snake

Venomous: No

The Western Worm Snake is one of the small snake species that live on the ground present in Illinois. This snake has some resemblance to the Midwestern Worm snake such as the pink belly or the small size as it grows up to 11 inches.

Western Worm snakes aren’t the easiest to spot as they spend most of their lives underground. These snakes are found on loose ground.

Most of what these snakes need is underground. This includes food and shelter. Earthworms are their preferred food.

Snakes of the genus are secretive. They mate in the spring and their young emerge in early summer but they also prefer underground habitats.

8. Northern Scarlet Snake

Northern Scarlet Snake

Scientific name: Cemophora coccinea copei

Common name: Northern scarlet snake

Venomous: No

The Northern Scarlet Snake is larger than the Western Worm snake, but it’s still considered a small species.

It’s identified by its red body with black and gray bands that make it a tricolored snake.

Much of the life of the Northern Scarlet Snake is unknown as it lives underground.

This snake only comes out to eat. It prefers lizards and various eggs it can find during the summer.

Highly common in the US, the snake isn’t present in the Northern states as its name implies. It mostly lives in Southern states such as Illinois, Louisiana, Georgia, Alabama, and Texas.

9. Kirtland’s Snake

Kirtland’s Snake

Scientific name: Clonophis kirtlandii

Common name: Cora Kennicott’s snake, Kirtland’s red snake, Kirtland’s water snake, little red snake, Ohio Valley water snake, Kirtland’s snake

Venomous: No

This family of snakes can grow up to 18 inches. It’s identified by a gray-black body but it’s not seen as frequently as other species since it lives underground.

Snakes of this genus are tied to water sources. This is the main reason they prefer swamps even if they can live in other dried habitats as well.

These snakes can eat all types of rodents and animals they can find from worms to toads.

Most people know them by their ability to play dead. The snake can remain motionless to fake its own death in the hopes the potential predator moves away.

The snake is also known to curl up in an attempt to fake its death. Its temperament is highly in the benefit of avoiding confrontation.

Its friendly nature towards humans is rarely tested as it tries to flee when seeing people.

10. Eastern Racer

Eastern Racer

Scientific name: Coluber constrictor

Common name: Eastern racer

Venomous: No

The Eastern Racer is a solid-color non-venomous snake that’s common in Illinois. This is the first type of snake that’s of medium size in terms of popularity in the state.

The Eastern Racer routinely grows up to 60 inches.

It’s known as an avid hunter and one of the agile snakes in the state. Unlike its name suggests, it doesn’t use constriction as a means to prey.

Instead, it pushes its body against the prey and a hard surface to overpower it.

This is how it catches rodents. It enters the nest of rodents and presses them against the walls to immobilize them.

These snakes then overtake the nest as one of the places to hide in from cold weather.

Snakes of the genus are also known as prolific breeders. Females lay up to 30 eggs at a time.

11. Ringneck Snake

Ringneck Snake

Scientific name: Diadophis punctatus

Common name: Ring-necked snake, ringneck snake

Venomous: No

Ringneck Snakes are common in the US. They live both in the North and in the South. Snakes of this group are identified by their olive-green bodies with a bright yellow band that goes around their necks.

The yellow neck ring of the species also serves as guidance for the male snakes. During the mating season, male snakes bite the female around the neck on this yellow line for easier mating.

There are 2 types of preferred habitats when it comes to Ringneck snakes.

Those living in Northern states such as Illinois prefer forests. Those living in Southern states go for riparian zones and high humidity environments.

Most Ringneck snakes are terrestrial. Some are even subterranean as it has been shown those living in Southern states often dig holes in the ground to escape the high summer heat.

In Illinois, these snakes are mostly found in dens with other Ringneck snakes.

12. Mud Snake

Mud Snake

Scientific name: Farancia abacura

Common name: Mud snake

Venomous: No

Mud snakes are normally associated with Southern states. However, this snake is common in the Southern regions of Illinois.

As their name suggests, they prefer marshes and high humidity habitats. However, they can be seen around areas of irrigation and other ditches with plenty of vegetation in the state.

They are a species of large snakes but are still rarely seen. These snakes have a shiny black body with either yellow or pink markings.

Mud snakes are always found next to water sources

13. Western Hognose Snake

Western Hognose Snake

Scientific name: Heterodon nasicus

Common name: Blow snake, bluffer, faux viper, plains hognose snake, prairie hognose snake, spoonbill snake, spreadhead snake, Texas hognose snake, Texas rooter, Western hognose snake

Venomous: No

The small Western Hognise species is endemic to North America. This snake is often confused with Rattlesnakes given it resorts to physical mimicry to appear a dangerously venomous species to its predators.

Western Hognose snakes aren’t dangerous. They only mimic strikes and make hissing sounds to appear more dangerous. These snakes can even raise their heads similarly to cobras to fend off potential predators.

Snakes of the genus grow to a size between 15 and 20 inches. While they have a small to medium body size, they are seen on rocky terrains and in river floodplains where they can eat all types of frogs.

Toads and lizards are also regularly consumed by this species when found next to rivers.

The Western Hognose snake isn’t particularly dangerous to humans. It tries to avoid confrontation as much as possible. If the snake cannot escape in time it might resort to playing dead when seeing people.

14. Eastern Hognose Snake

Eastern Hognose Snake

Scientific name: Heterodon platirhinos

Common name: Eastern hognosed snake, spreading adder.

Venomous: No

The Eastern Hognose species is also present in Illinois. The Western Hognose snake, it’s not considered a venomous species but a mildly venomous snake as its venom doesn’t impact people.

Like the Western Hognose Snake, the Eastern Hognose snake has venomous saliva it uses against its prey.

The snake is identified by its upward-facing snout as it comes in multiple colors such as black, grey, or red.

Like its Western counterpart, the Eastern Hognose snake is generally not aggressive. It has a few defense techniques to keep predators away.

It sometimes mimics a strike by hitting its prey with its snout. At the same time, this is one of the snake species in Illinois that knows how to play dead. It remains motionless to appear dead.

15. Prairie Kingsnake

Prairie Kingsnake

Scientific name: Lampropeltis calligaster

Common name: Prairie kingsnake, yellow-bellied kingsnake

Venomous: No

The Prairie Kingsnake is common in farmlands and woodlands. This snake species is perceived as not common as it’s nocturnal.

Prairie Kingsnakes heavily rely on their ability to pick up pheromones to guide themselves at night.

The species is known for eating insects when it’s young and for eating amphibians as it matures.

Prairie Kingsnakes live up to 10 years. They reach sexual maturity in the third year of their lives.

Most Prairie Kingsnakes also have predators, especially when they’re young. Skunks and possums are among the most common young Prairie Kingsnake predators.

16. Common Kingsnake

Common Kingsnake

Scientific name: Lampropeltis getula

Common name: Eastern kingsnake, common kingsnake, chain kingsnake

Venomous: No

The black Common Kingsnake is part of the Colubrid family of snakes. This species is mostly known for its capacity to hunt other snakes, especially venomous snakes.

Common Kingsnakes routinely eat Copperheads and Rattlesnakes. They are immune to their venomous bites.

Furthermore, Common Kingsnakes also eat other venomous species by clamping down on their jaws so that it has full control over a potential bite.

This snake is common in woodlands and on abandoned farms where it may feed on turtle eggs.

The species doesn’t carry live young as it lays eggs which take up to 2.5 months to hatch.

17. Milk Snake

Milk Snake

Scientific name: Lampropeltis triangulum

Common name: Milk snake, milksnake

Venomous: No

Milk Snakes are common in regions of Southern Canada and Illinois. These snakes are seen around farmland and water sources as they can swim.

The name of the species comes from its perceived desire to drink milk. This isn’t true as Milk snakes are carnivores.

Young Milk snakes eat all types of insects while adult Milk Snakes eat fish and lizards such as skinks.

Milk Snakes have more than 24 subspecies and many of them have different colors. White and red coloring with black and white bands are common among these subspecies.

18. Coachwhip

Coachwhip

Scientific name: Masticophis flagellum

Common name: Coachwhip, whip snake

Venomous: No

Coachwhip snakes are some of the fastest in Illinois. They move at speed of 4 miles per hour making them highly efficient at escaping predators.

These slender snakes can reach a total length of up to 100 inches. They are recognized for their thin bodies, small head, and large eyes.

Known as nocturnal, these snakes are not dangerous to people. They try to make the most of their speed to escape when seeing people.

On the other hand, they can bite as a mildly aggressive species. These bites can be dangerous if the bitten area develops an infection.

In terms of diet, rodents and lizards are preferred by Coachwhip snakes. They don’t have toxic saliva or constriction abilities to subdue prey. They use the strength of their jaws to grab prey and lock it in place.

19. Green Water Snake

Green Water Snake

Scientific name: Nerodia cyclopion

Common name: Green water snake

Venomous: No

This thick snake is known for its dark green dorsal color and its yellow underside.

Green Water snakes are common in the state’s marshes, lakes, and streams. It lives here so that it can find crayfish and fish to eat.

Snakes of the genus grow up to 35 inches and they mate at the end of the spring. Their eggs hatch by the beginning of August.

20. Plain-bellied Water Snake

Plain-bellied Water Snake

Scientific name: Nerodia erythrogaster

Common name: Plain-bellied water snake, plainbelly water snake

Venomous: No

The gray and green snake also has a yellow underside, similar to Green Watersnakes. The Plain-bellied Water Snake is known as an aquatic and semi-aquatic species.

In Illinois, it’s found next to lakes and rivers as well as in marshes. The species love to eat small fish, frogs, and salamanders.

At the same time, the Plain-bellied Water Snake is exposed to predation in its first year as a small snake.

Some of the most common predators of the species include fish. The Largemouth bass is one of the fish that regularly eats small Plain-bellied Water Snakes.

Other more venomous snake species are also known to prey on young snakes of the genus.

21. Banded Water Snake

Banded Water Snake

Scientific name: Nerodia fasciata

Common name: Banded water snake, Southern water snake

Venomous: No

The Banded Watersnake grows up to 62.5 inches. It comes in multiple colors such as gray and black with white or yellow bands around its body.

This species is sometimes confused with venomous snakes such as the Cottonmouth. However, it’s not a venomous snake.

Banded Water snakes prefer the habitat of still and freshwater streams and rivers. These are some of the snakes in Illinois that exclusively feed on fish and small reptiles found around water sources.

Unlike many other common snakes in Illinois, the Banded Watersnake doesn’t lay eggs as females of the species give birth to live young.

Even when going out to hunt at night these snakes can still detect prey. They have a gland that can detect the mucus on prey which guides them at night.

22. Diamond-backed Water Snake

Diamond-backed Water Snake

Scientific name: Nerodia rhombifer

Common name: Diamond-backed water snake

Venomous: No

This snake species is found next to streams and lakes. It comes in multiple colors but most snakes in the state are green with black stripes and lines on their body. The snake also has a yellow underside.

As an aquatic species, the Diamond-backed Water Snake is known to eat fish and all types of small amphibians found around water.

The snake often plunged into the water with its head to seek out small fish.

One of the largest concerns for the species is the human impact on its numbers. People often kill the snake thinking it’s venomous.

Many consider the species to be raised in captivity as well. It has a rather docile nature that allows it to be handled without biting.

23. Common Water Snake

Common Water Snake

Scientific name: Nerodia sipedon

Common name: Banded water snake, black water adder, black water snake, brown water snake, common water snake, common northern water snake, eastern water snake, North American water snake, northern banded water snake, northern water snake, spotted water snake, streaked snake, water pilot, water snake

Venomous: No

The Common Water Snake is one of the most aggressive species in Illinois. While the snake is not venomous, it’s known to bite.

Furthermore, the snake can bite several times when threatened or handled. It’s known to insert an anticoagulant which makes the bitten area bleed in excess. However, this is a small amount of anticoagulant for humans.

Known for its almost black appearance, this is also one of the largest snakes in Illinois. It always grows more than 4 feet.

The species is found near water sources. It’s known to be both diurnal and nocturnal. It can be seen resting in the sun during the day.

These snakes are also seen in the nests of muskrats which they consume as often as possible.

The young of the species are predated by foxes and opossums.

24. Rough Green Snake

Rough Green Snake

Scientific name: Opheodrys aestivus

Common name: Rough green snake

Venomous: No

The Rough Green Snake is one of the smallest green snakes in Illinois. This slender species is named after its vivid green dorsal color.

It can be seen frequently in woodlands and next to the water. It has a diurnal nature unlike many other species in Illinois.

Snakes of the species are known to live on the ground, on trees, and next to the water. Their versatility is given by their agile nature which is best seen when they quickly climb trees.

These snakes are generally friendly and they rarely bite. Their bite is not dangerous to people even when they decide to attack.

Snails are among its preferred prey. Rough Green Snakes are known for swallowing prey directly.

25. Smooth Green Snake

Smooth Green Snake

Scientific name: Opheodrys vernalis

Common name: Smooth green snake

Venomous: No

The Smooth Green Snake is commonly seen near permanent water sources. It’s a species that feeds on insects and spiders that live next to the water.

Most people identify the snake by its uniform green color. It lives in places that match this green color where it can use as camouflage.

Snakes of the genus grow to a maximum size of 14-15 inches. They are both diurnal and nocturnal and they rely on a sense of smell that picks up pheromones and chemicals to guide themselves together with vibrations.

People often see the species as the Smooth Green Snake that doesn’t necessarily like to run away when seeing humans.

26. Great Plains Rat Snake

Great Plains Rat Snake

Scientific name: Pantherophis emoryi

Common name: Brown rat snake, chicken snake, Eastern spotted snake, Emory’s Coluber, Emory’s pilot snake, Emory’s racer, Emory’s snake, gray rat snake, mouse snake, prairie rat snake, spotted mouse snake, Texas rat snake, Western pilot snake, great plains rat snake

Venomous: No

This gray patched snake is one of the largest in the state. It grows to a size of up to a few feet and it’s found in woodlands and next to woodlands in fields where mice and rats live.

Its diet mostly consists of rodents.

People are the biggest enemy of this snake as they confuse it with Rattlesnakes. The Great Plains Rat Snake also makes a hissing sound similar to the sound Rattlesnakes make.

While not venomous, the snake is still known to be aggressive. It becomes very active when seeing people and it bites at the first opportunity.

When not threatened the snake is lazy barely moving a few hundred yards each day. At most, it will move up to 200 yards per day.

27. Black Rat Snake

Black Rat Snake

Scientific name: Pantherophis obsoletus

Common name: Western rat snake, black rat snake, pilot black snake, black snake

Venomous: No

The Black Rat Snake is one of the large constrictor species in Illinois. It constricts its prey so that it cannot breathe anymore.

Snakes of the species are adapted to terrestrial and arboreal living. They prefer to live in trees, especially in woodlands where they freely move from one tree to another.

These snakes are some of the largest in Illinois as well. They grow to a maximum size of between 3 and 6 feet.

Unlike other non-venomous snakes, the Black Rat Snake lives in the same den as venomous snakes in the winter.

Some confuse it with venomous snakes. The Black Rate Snake is often confused with Rattlesnakes through its wiggly tail when it comes to being cornered.

It’s also an aggressive species that bites whenever it can.

Minks and hawks are among its preferred prey.

28. Western Fox Snake

Western Fox Snake

Scientific name: Pantherophis ramspotti

Common name: Western fox snake

Venomous: No

The Western Fox Snake is also known as the Fox Snake. It’s endemic to the Midwest US territories.

It lives in farmlands, crops, and other areas known for having rodents, which are its main prey. This species also eats frogs and lizards.

Snakes of the genus are identified by their dark grey patterns on dominant grey body color.

These snakes aren’t afraid to move in closer to homes, especially when chasing mice.

While not venomous, the species is aggressive. It hisses, shakes its tail, and it mimics strikes to appear more intimidating.

29. Eastern Fox Snake

Eastern Fox Snake

Scientific name: Pantherophis vulpinus

Common name: Foxsnake, Eastern fox snake

Venomous: No

If the Western Fox Snake lives in the upper Midwest, the Eastern Fox Snake is commonly found in North America.

They can be differentiated from the Western Fox Snake by their flat snouts.

Snakes of the genus grow up to 5 feet which makes them some of the largest in the state.

Often hiding in burrows, these snakes prefer pastures and farmland. It’s here they chase all types of rodents and rabbits as prey.

The snakes have been categorized as diurnal. However, they are very active at night during the summer months when access to prey is easier.

The name of the species is inspired by its odor. The snake has a similar smell to the North American Red fox.

30. Bullsnake

Bullsnake

Scientific name: Pituophis catenifer

Common name: Pacific gopher snake, Henry snake, coast gopher snake, bullsnake, Churchill’s bullsnake, Oregon bullsnake, Pacific pine snake, western bullsnake, western gopher snake, Sonoran gopher snake, western pine snake, great basin gopher snake, blow snake, and yellow gopher snake

Venomous: No

Bullsnakes are known to grow up to 8 feet. These are some of the largest snakes in the state.

Like most snakes in Illinois, Bullsnakes aren’t venomous. Snakes of the species are recognized by their yellow-black body with a small head and long snout.

Rodents, gophers, and ground squirrels are among the preferred diet of the snake. It also eats birds that nest on the ground.

Constriction is its main immobilization method.

The snake prefers not to bite people or other large predators. It rattles its tail similarly to Rattlesnakes as a defense mechanism.

The relationship between Bullsnakes and Rattlesnakes is more complex. Bullsnakes have been discovered to eat young Rattlesnakes.

31. Graham’s Crayfish Snake

Graham’s Crayfish Snake

Scientific name: Regina grahamii

Common name: Arkansas water snake, Graham’s leather snake, Graham’s queen snake, Graham’s snake, Graham’s water snake, prairie water adder, prairie water snake, striped moccasin

Venomous: No

This snake species is semi-aquatic. It lives next to various permanent water sources where it feeds on crayfish. Molting crayfish are among its preferred foods as they are easier to swallow.

Snakes of the species are identified by a brown dorsal. They’re known for growing up to a few feet with the longest discovered snake of the genus measuring 8 feet.

Found next to rivers and in marshes, these snakes aren’t venomous. They prefer to retreat to the water whenever seeing people.

Up to 15 eggs are laid at a time after the female Graham’s Crayfish Snake mates.

32. Queen Snake

Queen Snake

Scientific name: Regina septemvittata

Common name: Banded water snake, brown queen snake, diamond-back water snake, leather snake, moon snake, North American seven-banded snake, olive water snake, pale snake, queen water snake, seven-striped water snake, striped water snake, three-striped water snake, willow snake, yellow-bellied snake, queen snake

Venomous: No

Queen snakes are identified by their olive-green body with yellow stripes on their underside.

This is a small-medium species and it can grow up to 24 inches.

Similar to Graham’s Crayfish snake, the Queen snake is known for preferring to eat crayfish. Some studies suggest this species only feeds on crayfish.

Like Graham’s Crayfish snake, the Queen snake is known to prefer molted crayfish.

Habitat preferences for this species are considered among the most complex in Illinois.

Queen snakes are known to only live in environments with clean streams that have a rocky bottom and rocky surroundings.

33. Brown Snake

Brown Snake

Scientific name: Storeria dekayi

Common name: De Kay’s brown snake, De Kay’s snake, Brown snake

Venomous: No

Brown snakes are among the most common in the US. They are known to be small even if they occasionally grow up to 19 inches.

Most Brown snakes aren’t seen during the day. These nocturnal snakes come out at night when they prefer to eat slugs and snails.

Habitat preferences include loose soil areas. They live almost everywhere in Illinois with the exception of high altitudes.

34. Red-bellied Snake

Red-bellied Snake

Scientific name: Storeria occipitomaculata

Common name: Redbelly snake, red-bellied snake

Venomous: No

Red-bellied snakes are some of the most common in the US. They are present all over Illinois similarly to Brown snakes.

As Brown snakes, Red-bellied snakes eat many slugs to the extent they don’t want to eat any other prey.

These snakes are also small rarely growing longer than 9 inches.

Snakes of the genus are identified by their black dorsal and red belly.

As nocturnal species, these snakes only come out seeking snails at night. They might be found under rocks and leaves during the day.

Snakes of the genus have also been shown not to bite people when handled. Red-bellied snakes curl their snouts in a defensive mechanism when handled.

35. Flathead Snake

Flathead Snake

Scientific name: Tantilla gracilis

Common name: Flathead snake

Venomous: No

The Flathead snake is one of the smallest snakes in Illinois as it grows to a maximum length of 8 inches.

Its habitat has been considerably reduced as it lives in extreme locations in the Southern state.

These small snakes are known for preferring woodlands and rocky terrains next to woodlands.

A preference for woodlands habitats can be explained by their small size which is often subject to predators from above. A wide range of flying birds preys on this small snake.

36. Western Ribbon Snake

Western Ribbon Snake

Scientific name: Thamnophis proximus

Common name: Western ribbon snake, Western ribbon snake

Venomous: No

Western Ribbon Snakes are only slightly larger than Red-bellied snakes in Illinois. This species has been found in shrublands as well as in marshes and ditches where it gets to find frogs.

The Western Ribbon Snake is known to eat frogs. It has a unique hunting method that involves moving its head in 3 directions to mimic a strike and to drive frogs out of shallow water or from tall vegetation to grab them.

The snake is identified by a dark green body with yellow stripes that run from the head to the tip of the tail.

37. Plains Garter Snake

Plains Garter Snake

Scientific name: Thamnophis radix

Common name: Plains garter snake

Venomous: No

The Plains Garter snake looks similar to the Western Ribbon snake. It has a dark green body with white or yellow stripes that run from head to tail.

This species is common in the Midwest where it prefers meadows and prairies. These are fields with short vegetation close to water.

Snakes of the species aren’t considered venomous to humans. However, they produce and insert venom into small prey to immobilize it.

While rarely biting people, it cannot introduce a sufficient venom quantity to pose a real health risk.

38. Ribbon Snake

Ribbon Snake

Scientific name: Thamnophis sauritus

Common name: Ribbon snake

Venomous: No

Ribbon snakes can grow up to 35 inches. They are known for having a dark green-brown body which is used as camouflage in terrains with vegetation such as shrubs.

These snakes are known to guide themselves by sound and vibrations toward prey. They prefer not to eat warm-blooded animals such as mammals.

Instead, Ribbon snakes eat a wide range of amphibians. They consume salamander, toads, and frogs.

This type of prey is swallowed directly by the snakes which have large heads to allow easier feeding.

The reduced size of these snakes means that they are also seen as prey for large mammals.

39. Common Garter Snake

Common Garter Snake

Scientific name: Thamnophis sirtalis

Common name: Common garter snake

Venomous: No

The Common Garter snake is mainly recognized by its yellow lines that run across a green or black body.

The species is common in fields next to water sources such as marshes where it feeds on toads and frogs.

Unlike many snakes, the Common Garter Snake is known for eating the most poisonous toads as its immune to many types of neurotoxins.

In return, the snake also produces a small amount of venom that can be used against this prey but which isn’t dangerous to humans.

The snake is one of the most agile in the state. This allows it to consume other types of prey that move faster than the otherwise stagnant toad such as fish.

40. Lined Snake

Lined Snake

Scientific name: Tropidoclonion lineatum

Common name: Common snake, dwarf garter snake, grass snake, lined snake, ribbon snake, streaked snake, striped snake, swamp snake

Venomous: No

Lined snakes are found in parts of Illinois where it can find plenty of earthworms. Loose soil is needed for earthworms to live in a habitat.

These snakes are highly common in other states as well. It’s found in all states from Illinois to Texas.

Preferring soft soils with plenty of humidity, this species is rarely seen. It hides beneath leaves or it retreats in crevices or rodent nests when encountering people.

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