Lizards are reptiles. Reptiles are animals that have a backbone, dry skin and are covered with scales or bony plates. Their body temperature is controlled by the outside temperature and by their behavior. Some of them produce soft-shelled eggs that develop on land. They have four limbs or are related to ancestors that had four limbs. Lizards have a long body with a long tail. They have movable eyelids. Their lower jaw is fused (the two sides don’t move separately), and they have external ears. Male lizards are often territorial and fight other male lizards. There are eight species of lizards known to live in Illinois. Two of them are not native to the state.
As an avid nature lover living in Illinois, I’ve always been fascinated by the diverse wildlife found in the Prairie State. One unique group of animals that many don’t realize inhabit Illinois are lizards.
Lizards are remarkable reptiles that have managed to thrive in a variety of environments, including the prairies, forests, and wetlands of Illinois. In this complete guide, I’ll cover everything you need to know about the lizards that call Illinois home, from identification and behavior to the best places to spot them.
There are 6 native lizard species found in Illinois along with 1 introduced species. The lizards inhabiting Illinois range in size from just a few inches to over 3 feet in length!
The most commonly seen lizards in the state belong to the skink family Skinks are smooth-scaled lizards with elongated bodies and reduced limbs Three skink species reside in Illinois the broad-headed skink, common five-lined skink, and little brown skink.
Other native Illinois lizards include the six-lined racerunner, eastern fence lizard, and slender glass lizard The Mediterranean house gecko is the only non-native lizard species found in the state
Lizards fill an important ecological role in Illinois as predators of insects, spiders, and other small invertebrates. Their diverse diets help control pest populations. Some larger lizard species will even eat small rodents and other lizards!
Identifying Lizards in Illinois
Correctly identifying the lizards you come across in Illinois can be tricky. Lizards can easily be mistaken for snakes or other reptiles at first glance.
Here are some key identification features to look for:
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Eyelids – Lizards have movable eyelids unlike snakes which have fixed transparent scales over their eyes.
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Legs – Lizards have 4 legs while snakes lack legs entirely. Some legless lizard species like the glass lizard may resemble snakes though.
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Scales – Lizards have small, smooth scales over their bodies. Snakes have larger, overlapping scales.
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Body Shape – Most lizards have a flattened body and head whereas snakes have a cylindrical shape.
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Tail – Many lizards can detach their tails when threatened. Snakes do not have detachable tails.
Let’s take a closer look at how to identify each of the 7 lizard species found in Illinois:
Six-lined Racerunner
The six-lined racerunner is aptly named for the 6 yellow or green stripes running the length of its dark brown body. They have a white underside and long blue tales. These lizards reach 2.5-4 inches in length and are very quick, speeding up to 18 mph when threatened!
Eastern Fence Lizard
Eastern fence lizards are brown or gray with a pale belly. They have a dark stripe behind their thigh and males have blue patches on their throat and belly. They reach 2-3.5 inches long and are found in forests basking on logs and rocks.
Common Five-lined Skink
As the name suggests, five-lined skinks have five distinct white or yellow stripes down a black or brown body. The tail is bright blue in juveniles. Males develop orange jaws during breeding season. They grow up to 9 inches long.
Broad-headed Skink
The broad-headed skink is a heavy-bodied lizard reaching over 12 inches in length. They are brown or olive with faint striping in juveniles that fades with age. Males develop orange heads when breeding. Their triangular head is a key ID feature.
Little Brown Skink
A small lizard less than 6 inches long, the little brown skink is brown or black with a yellowish underside. They lack prominent stripes and love hiding among leaf litter on the forest floor.
Slender Glass Lizard
Glass lizards have long, snake-like bodies that can reach 3 feet in length. Their brown scales have pale flecks that may form stripes along the back. When threatened, the tail easily detaches.
Mediterranean House Gecko
The only non-native lizard in Illinois, these geckos have tan bodies with dark spots and stripes. Large eyes with vertical pupils and suction cup toes help them climb walls and ceilings. They are nocturnal and reach just 2-3 inches long.
Where to Find Lizards in Illinois
Lizards inhabit a variety of habitats in Illinois. Here is a brief overview of where to spot each species:
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Six-lined Racerunners – Open habitats like prairies, fields, and rocky areas.
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Eastern Fence Lizards – Forests, parks, and backyards, often seen on fences.
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Common Five-lined Skinks – Forests with fallen logs and other woody debris.
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Broad-headed Skinks – Swamp forests and wooded urban areas.
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Little Brown Skinks – Leaf litter in forests and wooded edges.
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Slender Glass Lizards – Prairies, fields, and sandy areas.
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Mediterranean House Geckos – On buildings and urban structures.
The southern half of Illinois tends to harbor more lizard species given the warmer climate. But you may find southern species like broad-headed skinks increasingly extending their range northward as temperatures rise.
Gardeners may find small lizards like skinks in the mulch beds, compost piles, and rock walls around their yard. Keep an eye out when tackling yard work.
Behavior and Ecology
Lizards exhibit some fascinating behaviors and adaptations for life in Illinois:
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Basking – Lizards are cold-blooded reptiles that rely on external heat to regulate their body temperature. You’ll often see them “basking” in sunny spots on logs, rocks, walls, and other structures to absorb heat.
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Shedding Skin – To enable growth, lizards have to regularly shed their outer layer of skin. The skin peels off in patches over a period of days or weeks.
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Detachable Tails – Many lizards will detach all or part of their tail to escape predators. The tail will regrow over time, though never quite the same as the original.
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Territoriality – Male lizards often defend a territory against intruding males, using head bobs, push ups, and even physical combat.
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Egg Laying – Female lizards lay soft-shelled eggs in underground nests, rotting logs, or under debris. Mothers of some species will guard the eggs until hatching.
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Hibernation – Lizards in Illinois hibernate underground through the winter months when temperatures get too cold for their activity.
Conservation Status
Fortunately, most lizard species in Illinois are thriving with stable populations statewide. The six-lined racerunner is listed as endangered in Illinois since its habitat has declined significantly. Protecting and restoring prairie habitats will help support these speedy lizards.
The greatest threat to Illinois lizards is habitat loss as natural areas are replaced with development. Pesticide use can also impact lizard populations by reducing their insect food sources.
You can support lizards in our state by creating wildlife habitat at home. Planting native plants, leaving brush and leaf litter, and constructing rock piles in your yard gives lizards places to hide, bask, and hunt. Limiting pesticide use will provide a bounty of insects for them to feed on.
Enjoying Illinois’ Lizards
Now that you know the basics about Illinois’ lizard inhabitants, you’ll be ready to spot these remarkable reptiles on your own adventures in nature.
With some luck and patience, you may catch sight of a six-lined racerunner zipping by or a little brown skink scurrying through last fall’s leaves. Always be respectful of wildlife and observe lizards from a distance to avoid stressing them.
Family and Species Gallery
Kingdom: Animalia – Animals are multicellular organisms that rely on other organisms for nourishment. There cells do not have cell walls. Most animals are capable of movement at least in some portion of their life cycle. Reproduction is generally sexual, but in some animals asexual reproduction may be utilized at certain times. Phylum: Chordata – The Phylum Chordata contains the vertebrate animals. Mammals, birds, reptiles, amphibians and fishes are included in this phylum. These animals have a notochord at some point in their development. They have a tubular nerve cord along the back. Gill slits and a tail are present at some point in their life cycle. They have an internal skeleton. Class: Reptilia (lizards, snakes and turtles) – These organisms develop from and amniotic egg, which is either deposited on land or retained within the female for the extent of its development. The egg provides everything the embryo needs to develop. The shell of a reptile egg is leathery. Fertilization is internal. Reptiles are covered in scales, and their skin is dry. Order: Squamata (lizards and snakes) – The lizards and snakes have dry, scaly skin. Their lower jaw is attached by a special bone that allows the mouth to open very wide. Family: Anguidae (Glass Lizards) – The glass lizards have a bony plate in each scale and a groove along each side of the body. The long tail is easily broken off the body. slender glass lizard (Ophisaurus attenuatus)
Family: Phrynosomatidae (Sagebrush and Spiny Lizards) – These lizards have teeth along the lower jaw. They communicate with each other by body movements. eastern fence lizard (Sceloporus undulatus)
Family: Teiidae (Racerunners and Whiptails) – Racerunners and whiptails are medium-sized lizards. They have a long tail. The scales on the body are tiny. six-lined racerunner (Aspidoscelis sexlineata)
Illinois Lizards
FAQ
Are there wild lizards in Illinois?
There are eight species of lizards known to live in Illinois. Two of them are not native to the state. Your Browser does not support HTML5 Video tag or the video cannot be played.
Is it good or bad to have lizards in your yard?
… in your garden can prove that your garden (and any food grown in it) will have low levels of pesticides, heavy metals, and potentially harmful chemicals
What type of lizards live in your backyard?
However, the types of lizards that do frequent populated areas persistently invade homes. Western fence lizards, house geckos, and brown or green anoles are experts at squirming through cracks around windows, doors, and foundations. Green iguanas are also a common sight around lawns, patios, and swimming pools.
Are lizards OK around the house?
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Natural pest control:Lizards, particularly geckos, are known to consume various insects, reducing potential pest infestations.
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May not be a threat to your home:Unlike some other pests, lizards typically don’t cause structural damage to houses, according to a post on Reddit.
Which lizards live in Illinois?
Six-Lined Racerunners are one of the seven types of lizards found in Illinois. They can be spotted in various habitats, such as grasslands, rocky terrain, wooded areas, and floodplains. Six-Lined Racerunners are insectivores, with termites being their primary food source.
Do any lizards in Illinois look like snakes?
Some lizards in Illinois can look like snakes, which can be concerning if you have pets or children at home. It’s always useful to be able to identify the lizards in your backyard or local area. Continue reading to get detailed information on the 6 lizards you may come across in Illinois. 1. Slender Glass Lizard
Is there a gecko species in Illinois?
The Mediterranean House Gecko is not a native species in Illinois, but it was introduced via imported plants carrying their egg clutches. They are adaptable to various environments and their population has grown significantly in Illinois, outpacing any of our native geckos.
What is a little brown skink lizard?
The little brown skink, also known as a ground skink, is a small lizard growing up to 5.5 inches or 14.5cm from nose to tail. It is copper brown in color with a white or yellow underbelly. This lizard has an elongated body, sort legs, and can be found in forests, hedges, on the edge of ponds and streams, and within leaf litter.
Do eastern fence lizards eat fire ants?
Eastern Fence Lizards forage for food, which includes insects like ants, beetles, and grasshoppers. In Illinois, they have adapted to the presence of fire ants.
What does a six-lined lizard look like?
The six-lined racerunner is a lizard with six green/yellow or yellow stripes that run from the head to the tail. They are typically dark green, black, or brown, and females have a white belly, while males are pale blue with a light green throat. The males also have a double the length of their slender bodies for a long tail. The six-lined racerunner is a dark green, black, or brown lizard. Females have a white belly, while males tend to be pale blue. The males also sometimes have a light green throat, and their tail is twice the length of their body.