Coal Skink

A coal skink is a small, secretive lizard from the eastern United States. It carries a wide dark stripe down each side of its body. It dives straight into water when threatened.

Plestiodon anthracinus lives under rocks and leaf litter on damp, wooded slopes. It rarely basks in the open the way a five lined skink does. Its range is patchy, and several states track it as a species of conservation concern.

This guide covers how to identify one, where it lives, and what it eats. It also covers how it breeds and why it is not a starter reptile from a pet store. Two subspecies exist, the northern coal skink and the southern coal skink.

Identifying a Coal Skink

The species has smooth, glossy scales and short legs for its body length. Four narrow, light colored stripes run from the head toward the tail. They sit against a dark brown or blackish background.

The key field mark is the lateral stripe. It spans roughly 2.5 to 4 scale rows on each side. That is wider than the lateral stripe on a five lined skink.

It also lacks pale stripes on top of the head. Most five lined skinks carry those head stripes. That single difference settles most identification questions in the field.

Breeding season brings a visible change in adult males. Their cheeks flush reddish orange from late winter into spring. Juveniles often look almost solid black or show faint striping.

Hatchlings are black with faint lines and a blue gray tail, according to the Missouri Department of Conservation. That tail is duller than the vivid blue of five lined and broad headed skink hatchlings.

The two recognized subspecies differ slightly in range. The northern coal skink, Plestiodon anthracinus anthracinus, occupies the Appalachian corridor. That range runs from parts of New York and Pennsylvania south into the Carolinas.

The southern coal skink, Plestiodon anthracinus pluvialis, ranges further south. It reaches into the Gulf coastal plain and south central states.

Where the two forms meet, coloring can look intermediate. A clean subspecies call is often hard to make without a specimen in hand. Most field guides treat this as a zone of overlap rather than a hard boundary.

Habitat and Range

These skinks favor moist hardwood forest, especially north facing slopes. They also use seepage areas near springs and small streams. Rocky bluff edges with plenty of cover work too.

Flat rocks, logs, and leaf litter all matter as cover objects. In New York, surveyed animals stay within about 50 meters of water. The species will use lawns and powerline cuts if enough cover and moisture remain nearby.

The overall range covers the eastern half of the United States. Populations are fragmented rather than continuous across that range. New York sits at the far northern edge and holds only a small share of the total distribution.

Habitat patches often sit far apart from each other. Because of that spacing, a local population can vanish after one bad year. No nearby population may exist to replace it.

What Coal Skinks Eat

This lizard is an opportunistic insectivore. It forages through leaf litter and under cover objects rather than climbing or basking in the open. Confirmed prey includes termites, ant larvae and pupae, earthworms, and spiders.

The diet also includes a range of small soft bodied insects. Prey size stays small and soft, matching the skink’s own modest size. Feeding happens mostly in cool, shaded, moist ground rather than in direct sun, and Missouri notes that young ones take termites readily.

This diet and foraging style is one reason the species is hard to keep long term. The live insect variety it needs is difficult to source on a fixed schedule. The constant moisture it relies on is just as hard to replicate in a terrarium.

Size and Lifespan

Adults measure 5 to 7 inches in total length, tail included. That makes them one of the smaller skinks native to the eastern United States. Hatchlings emerge at about 2 inches and grow quickly through their first year.

Growth slows once an animal reaches sexual maturity. No state agency or database opened for this profile publishes a wild lifespan for the species. Related Plestiodon skinks in temperate climates are generally reported to live several years in the wild.

Some individuals survive longer under good conditions. No verified captive longevity record exists for this species. It is essentially never kept as a long term captive, so there is no large sample of ages to draw from.

Behavior and Defense

These lizards spend most of the day hidden under rocks, bark, and leaf litter. They emerge to forage during humid or overcast conditions rather than in direct sun. Disturb one and its first move is usually a sprint toward the nearest water.

Once in the water, it dives beneath a submerged rock or debris pile to hide. North Carolina’s wildlife agency notes this water diving escape as a distinctive habit. Few other eastern skinks do it so readily.

The species carries no venom and poses no threat to people. A cornered adult can deliver a small pinching bite if handled. That bite is a defensive reflex, not aggression, and it will not break human skin in any real way.

Like many skinks, it can also drop its tail if a predator grabs it. It will regrow a shorter, duller replacement over the following weeks.

Reproduction and Eggs

Mating happens in late winter or early spring, around the time males develop their reddish breeding cheeks. Females lay one clutch of 4 to 9 eggs per season, or 4 to 10 in Missouri, during May and June. Eggs go into damp soil, usually under a flat stone or a rotting log.

Moisture around the eggs has to stay steady through incubation. Females guard the nest for roughly 4 to 5 weeks, or 28 to 35 days by Missouri’s figure. Hatchlings typically emerge around July or August, depending on when mating occurred that year.

This maternal guarding behavior appears in several other Plestiodon species. It likely cuts egg loss to small predators. It may also protect the clutch from mold in the humid nest environment.

Health, Threats, and Predators

In the wild, these skinks face predation from snakes, birds, and small mammals. Juveniles are also vulnerable to larger invertebrates and to other lizards. Tail loss is a common survival response to an attack, not a sign of poor health on its own.

Conservation assessments point to a consistent set of threats. Habitat loss from development tops the list. Fragmentation that isolates small populations from each other adds to the problem.

Road mortality is a factor as animals cross between forest and water. Illegal collection for the pet trade still happens in some areas. Contaminant exposure near seepage habitats adds further pressure.

New York’s most recent species status assessment describes local populations as small and scattered. A single severe event could wipe out a local population outright. A habitat altering flood or a new development project would qualify.

Population trend assessments generally describe the species as stable to possibly declining. Some historically documented sites have not been reconfirmed in recent surveys. The species has also turned up again in counties where it had not been recorded for years.

That kind of reappearance suggests detection difficulty plays a role alongside any real decline.

Legal Protection and the Ethics of Keeping a Coal Skink

This species is not a pet store animal. It is not legally available through the normal reptile trade. The species carries no federal listing under the Endangered Species Act.

Individual states regulate it more strictly than federal law does. Tennessee lists it as very rare and imperiled, while Missouri considers it secure.

New York classifies the northern coal skink as a species of greatest conservation need. Its state rarity rank there runs from imperiled to vulnerable.

Collection permits in New York go only to scientific or conservation projects. Personal keeping is not an option under that system. Rules vary by state and can change over time.

Anyone who finds one should check current regulations with a state wildlife agency first. That applies before disturbing, handling, or collecting one. Do not assume a lizard found in the yard is free to keep.

Removing animals from a small, fragmented population for a hobby terrarium works against the same conservation goals every state wildlife agency is trying to protect. The animals most people will ever see up close live in accredited zoos, universities, or state wildlife programs. Those institutions hold proper scientific permits.

Such institutions can show a documented, disease screened source for each animal. They also carry a plan for its long term welfare. A wild caught pet or a backyard capture cannot offer either one.

If you want hands on experience with a skink, our guide to skink care covers species that are legally captive bred and well suited to home keeping.

The five lined skink and great plains skink profiles cover two relatives worth comparing once you know what to look for. Both are also wild natives rather than pets.

What a Permitted Keeper or Zoo Provides

When an institution does hold a legally permitted animal, the setup mirrors the wild microhabitat. That looks nothing like a typical desert or tropical terrarium. Enclosures use a deep, moisture holding substrate, such as a coco fiber and sphagnum moss blend, kept damp but not soaked.

Flat stones, cork bark, and leaf litter get stacked to recreate the layered cover the species relies on. A shallow water dish large enough to fully submerge in matters more here than for most terrestrial skinks. The animal dives underwater readily to escape a threat.

Our general skink enclosure guide and skink habitat overview cover the broader setup principles. For this species, shift those toward higher humidity and cooler temperatures. A typical five lined or blue tailed skink setup runs too warm and too dry.

Temperature and Lighting Needs

These skinks come from temperate forest habitats, not tropical or desert climates. Their natural temperature range runs cooler than many popular pet lizards. Wild activity happens in ambient conditions roughly between 60 and 80 degrees Fahrenheit, shifting with the season.

Animals retreat deeper under cover during summer heat spikes and winter cold. They do not bask to raise body temperature the way sun loving lizards do.

A permitted keeper replicates this with a mild ambient gradient. Dappled, filtered light works better than an intense basking bulb. A natural seasonal cool down period supports normal breeding cycles in institutional collections.

This is a different approach than the setup described in our types of lizards overview for basking species. The biology here simply does not call for the same setup.

Cost of a Coal Skink

There is no retail price for this lizard, because the species is not sold commercially. It does not appear in the pet trade price lists that cover captive bred skinks. Any ad offering one for sale should be treated as a red flag, not a bargain.

The real costs tied to this species fall on institutions and researchers. State and federal collection permits carry a cost, as does habitat survey work. Long term monitoring programs add further expense, paid by agencies and universities rather than hobbyists.

For someone drawn to this species’ look and habits but wanting a legal animal to keep, the picture looks completely different with a captive bred species. Our skink diet guide and broader lizard feeding guide both apply to legally available skinks from a reputable breeder.

Frequently Asked Questions

Is a coal skink poisonous or venomous?

No. It carries no venom and poses no danger to people. A cornered adult may pinch with its jaws, but the bite is harmless.

How can I tell a coal skink from a five lined skink?

Check the head and the lateral stripe. The coal skink lacks pale stripes on top of the head and shows a wide dark lateral stripe spanning 2.5 to 4 scale rows. A five lined skink usually carries head stripes, a narrower lateral stripe, and a bright blue juvenile tail.

Can you legally keep a coal skink as a pet?

In most states, no. They are wild, often locally rare, and are not part of the legal pet trade. Collecting one without a scientific or educational permit can break state wildlife law.

What does a coal skink eat in the wild?

They eat small invertebrates found in leaf litter and damp soil. Termites, ant larvae and pupae, earthworms, and spiders make up most of the diet. They forage in shaded, moist ground rather than hunting in open, sunny spots.

How many eggs does a coal skink lay?

A female typically lays one clutch of 4 to 10 eggs per season, hidden under a rock or log in damp soil. She guards the nest through an incubation period of about 4 to 5 weeks. Hatchlings usually emerge in July or August.

Why are coal skink populations considered vulnerable in some states?

Its habitat sits in small, disconnected patches rather than continuous forest. That fragmentation, combined with development and road mortality, leaves some state populations very small. A single disruptive event could wipe one out.