Six Lined Racerunner

The six lined racerunner (Aspidoscelis sexlineata) is one of the fastest lizards in North America. It is a slender teiid that sprints across open ground in the eastern and central United States. It gets its name from the six pale stripes running down its back, a pattern that helps separate it at a glance from the five lined skink it is often confused with.

This is a wild, protected species in most states, not a pet. This guide covers its biology, its legal status, and why captivity is a poor fit for the animal.

Identification and how it differs from a whiptail or skink

The six lined racerunner belongs to the whiptail family, Teiidae. That is the same group covered in our whiptail lizard overview. Whiptails and racerunners share a long, tapering tail and granular back scales.

They also share a constant, jerky foraging motion. Read the family overview first for the broader picture, then come back here for species detail.

Six adult stripes run from the head onto the base of the tail. They are usually yellow, cream, or pale blue against a dark brown, black, or olive background. Juveniles often show a bright blue tail that fades with age.

The belly scales are large and rectangular, arranged in eight straight rows. The throat has two skin folds. That combination rules out the five lined skink covered in our five lined skink guide.

A skink has smooth, glossy, overlapping scales and a shorter, thicker tail. It also moves with a smooth glide rather than the racerunner’s stop and dash sprint. Adult total length runs 6 to 9.5 inches, or 15.2 to 26.7 centimeters.

Males are typically larger than females. The tail accounts for roughly 70 percent of that total length, according to Animal Diversity Web. A racerunner missing part of its tail looks unusually short bodied as a result.

Range, habitat, and why it needs open ground

The species ranges through the southeastern and central United States. It runs from the Mississippi River valley east into the Carolinas and south through Florida. Populations extend west into the Great Plains as prairie racerunners.

It lives in savannas, sandhills, coastal dunes, and fire maintained pine woodlands. It also uses old fields and rocky, sun exposed slopes, generally below about 650 meters elevation. Every one of those habitats shares open, sparsely vegetated ground with loose or sandy soil.

That open ground gives the lizard full sun exposure and enough bare patches to see predators coming. A racerunner can then outrun them in a straight line. Its home range is roughly 800 square meters.

It patrols that space in short, explosive bursts rather than a steady walk. This matters for anyone thinking about captivity. A terrarium, even a large one, cannot reproduce the distance a racerunner needs to run at full speed.

That inability to sprint is a documented source of chronic stress in fast, open country lizards kept in tanks.

Thermal needs in the wild

Racerunners are strict heliotherms. They bask directly on open sand, rock, logs, and even pavement. Basking pushes their body temperature well above the surrounding air temperature.

They retreat to burrows or vegetation once they overheat. They are active only on warm, sunny days and disappear entirely during cool, overcast weather. In the northern and central parts of the range they hibernate underground through the coldest months.

They choose south or southwest facing slopes for that winter burrow. They emerge again in spring once soil temperatures rise. A licensed facility replicating this needs intense basking heat, close to what desert dwelling lizards receive.

It also needs strong UVB across a large horizontal basking area, plus a cool retreat and a winter cooling period that mimics natural brumation. Most home terrariums cannot deliver that basking intensity or that UVB gradient. That is one more reason this species belongs in the field or in an accredited zoo, not a spare bedroom tank.

Diet: what it actually eats

Racerunners are opportunistic insectivores that forage constantly across open ground. They flick their tongues to track scent trails left by prey. Grasshoppers, crickets, beetles, spiders, and ants make up most of the diet.

Termites are a particularly important food source where they are locally abundant. Racerunners also take moths, caterpillars, and other soft bodied invertebrates when available.

This diet is entirely wild caught and highly varied by season and location. That is another reason racerunners do poorly on the narrow rotation of feeder insects available to a home keeper. A captive diet built from crickets and mealworms alone does not match the breadth of what this species eats in nature.

Health, predators, and threats in the wild

Northern black racer snakes are a documented predator. Fire ants attack racerunner eggs and hatchlings directly, and that threat has expanded as invasive fire ant populations have spread through the southeastern range. Habitat loss from development is the larger long term pressure on many local populations.

Fire suppression adds to that pressure, since it lets woody vegetation close over the open sandy ground this species needs. The species as a whole is not considered globally threatened. A racerunner that loses part of its tail to a predator will regrow a shorter, often differently colored replacement.

That regrowth is a normal defense mechanism, not a sign of illness. This is a wild species without an established captive medicine literature. Anyone who finds an injured or sick racerunner should contact a wildlife rehabilitator or a reptile veterinarian rather than attempting home treatment.

Behavior and speed

These lizards are diurnal and solitary. They stay active on the ground during the warmest, sunniest parts of the day. They forage in short, quick bursts, stopping to probe leaf litter and loose soil, then sprinting to the next patch of open ground.

That movement pattern is the defining behavioral trait of the species. It runs in short intense sprints interrupted by pauses, not sustained running. The North Carolina Wildlife Resources Commission puts its top speed at up to 18 mph.

That places it among the fastest lizards in North America. The University of Georgia’s Savannah River Ecology Laboratory calls it one of the most difficult lizards to capture, and notes it stays active even on the hottest summer days. Its long tail and legs make it very difficult for most predators to catch in open terrain.

During spring courtship, males develop brighter throat and chest coloration. They display that color to females and to rival males. Outside the breeding season, racerunners show little social behavior beyond overlapping home ranges and occasional territorial encounters between males.

Breeding, eggs, and subspecies

Breeding takes place in spring and early summer. Females produce one to three clutches per year. Clutch size varies by subspecies and locality.

It typically runs from about three to five eggs in the nominate eastern form, with state agencies reporting 1 to 5 eggs in Georgia and South Carolina and 2 to 8 in North Carolina. Some prairie racerunner clutches hold as many as eight eggs. Eggs are laid in shallow burrows dug into loose soil, or sometimes in sawdust piles.

Hatching takes roughly five to eight weeks, depending on soil temperature. Study conditions have recorded incubation periods of 36 to 40 days. Field reports from Missouri and Tennessee note hatching about 60 days after laying, so the study figure reflects warm, controlled conditions.

In North Carolina, hatchlings emerge from late June through early September. Sexual maturity is reached at one to two years of age.

The eastern form shows six stripes and a background of black, brown, or olive. The prairie racerunner subspecies, Aspidoscelis sexlineata viridis, often shows seven pale stripes instead of six. It is found through Missouri, the southern Great Plains, and along major river corridors farther north.

Breeding males of the prairie subspecies develop a wash of bright green over the head and shoulders that the eastern form lacks. Females of that subspecies have salmon pink to creamy white bellies. Both forms share the same general biology, diet, and behavior.

Both are properly identified using the overview at our types of lizards guide, alongside a good regional field guide. Stripe count and color can vary within a single population, so identification sometimes needs more than one field mark.

Lifespan and size

Wild racerunners have a documented maximum longevity of about 6 years. Average life expectancy in the wild is much shorter, closer to 2 years. That reflects heavy predation pressure on a small, fast moving lizard that spends its entire life exposed on open ground.

This sits toward the shorter end of what is typical across small lizard species generally. Our lizard lifespan guide covers how that compares across other groups. Adults reach 6 to 9.5 inches in total length, with most of that length made up of tail.

Hatchlings are only a couple of inches long. They grow quickly through their first active season. Most populations reach adult size within about a year.

Legal status and the cost of keeping wildlife

This species is native wildlife, not a captive bred pet, so there is no commercial trade or price to quote here. Collecting, possessing, or transporting native reptiles is regulated at the state level in the United States. Most states within the racerunner’s range require a permit to collect wild reptiles, cap the number that can be taken, or prohibit collection outright depending on the state and the land involved.

Some protected natural areas ban all wildlife collection, regardless of the state’s general hunting or fishing rules. Anyone who wants to know whether keeping a racerunner is legal in a specific state needs to check that state wildlife agency’s current reptile and amphibian regulations directly. Those rules vary by state and change over time.

Beyond legality, welfare is the bigger issue. This is a heliothermic sprinter built to cover an 800 square meter home range in short, explosive dashes across open, sun baked ground. No home terrarium, however large, gives a racerunner room to run at speed.

The species has no established history of thriving in captivity the way many pet trade lizards do. Zoos and accredited educational facilities that display racerunners typically use large outdoor or greenhouse style enclosures. Those setups include real substrate, intense basking heat, and enough open floor space for the animal to sprint the way it does in the wild.

A standard glass tank cannot replicate any of that. The honest recommendation for most people who want to enjoy this species is to watch it in the wild, where it belongs, rather than to remove it from its habitat.

Frequently Asked Questions

Is a six lined racerunner the same as a whiptail lizard?

Yes, in the sense that both belong to the whiptail family, Teiidae. It is one specific whiptail species native to the eastern and central United States, distinct from the larger western whiptail species covered in our whiptail lizard guide.

How can I tell a six lined racerunner from a five lined skink?

Look at the scales and tail shape. A racerunner has small, granular back scales and a long, thin, whip like tail, while a five lined skink has smooth, glossy, overlapping scales and a shorter, thicker tail. Racerunners also move in quick sprints and pauses, while skinks move with a smoother, continuous glide.

Can you legally keep a six lined racerunner as a pet?

It depends entirely on the state. Most states within its range regulate or restrict collecting native reptiles, and some protected areas ban collection outright, so anyone considering it needs to check that state’s current wildlife agency rules before taking one from the wild.

How fast can a six lined racerunner run?

Up to 18 mph, according to the North Carolina Wildlife Resources Commission. It relies on short, explosive sprints across open ground rather than sustained speed, and it retreats to a burrow once it has put distance between itself and a threat.

What does a six lined racerunner eat?

It eats a wide range of ground dwelling insects and spiders, with grasshoppers, beetles, ants, and termites making up most of the diet. Termites are especially important where they are locally common.

How long do racerunners live?

The documented maximum in the wild is about 6 years, but average life expectancy is closer to 2 years due to heavy predation on a small, exposed, fast moving lizard.