The southern coal skink is secretive and few people know about it. It lives in the southern half of Missouri, excluding the Bootheel. It is small, shiny, and brownish tan, with broad, dark stripes running along the sides. The general color is tan, brown, or olive brown. The broad stripe on the side can be brown or black; it is bordered by a thin light line above and below and is 2–4 scales wide. There are no light stripes on the head. The chin normally has a single postmental scale, but occasionally some Missouri individuals may have two postmental scales (these are center-line scales behind the mental scale on the chin; the mental scale is the first center-line chin scale, counting from the front).
During the breeding season, adult males have dark orange on the sides of the head.
Hatchlings are black with faint lines running along the back and sides and a blue-gray tail. (Note that the juveniles of some other skink species also have black bodies with blue tails.)
Adult length: 5 to 7 inches.
Restricted to the southern half of the state, except for the Bootheel.
Habitat and Conservation
In Missouri, the southern coal skink is active from mid-March to early October; it is most easily found in April. It occurs in forests and woodlands, in habitats ranging from moist streamside bottomlands to drier rocky hillsides. Preferred locations are open, damp, rock-strewn woods where it takes shelter under rocks, logs, leaf litter, or bark. During spring, they are commonly found on open, rocky glades along hillsides. They also inhabit rock quarries and rocky roadcuts. During the winter, they likely retreat underground into rocky crevices and animal burrows and beneath large rocks.
Few people know about this shy lizard. It becomes active midmorning on sunny days but quickly takes shelter in dead leaves or under rocks or logs when approached. Coal skinks sometimes run into small steams to avoid capture.
This species eats a variety of small insects and spiders. Young southern coal skinks readily eat live termites.
Although the southern coal skink is seldom seen compared to other woodland skinks in Missouri, the species appears to be secure.
Courtship and mating occur from April through May, and egg laying takes place during May and June. A female will lay 4–10 eggs, presumably beneath rocks and logs. The eggs are about ½ inch long and are guarded by the female until they hatch around 28–35 days later. Hatchlings are about 2 inches in length. Individuals likely reach sexual maturity in two years.
Human conservation efforts are important for the future of this and many other species in our state. Maintaining glades and adjacent rocky wooded hillsides will ensure this species remains common throughout the Ozarks of Missouri.
Skinks are among many reptiles that easily shed their tails and regrow new ones. This self-amputation is called autotomy. Scientists studying the molecular and cellular workings of tail regeneration in lizards may one day help humans overcome spinal cord injuries.
Like most other lizards, this species preys on insects and other small animals and therefore helps maintain their numbers in a natural balance.
This skink is preyed upon by a number of larger predators. The tail of a skink can easily be broken off as protection from a predator. Natural predators for this species include snakes, large lizards, birds such as shrikes and hawks, and mammals such as badgers and skunks. Domestic cats are also known to capture and eat small lizards.
The skinks (Scincidae) are a large family of lizards with species on nearly every continent and many oceanic islands. There are over 1,580 species worldwide, representing about 115 genera. The smallest species may be only 3 inches long; the largest (in Australia) may reach a length of over 2 feet. Most species have smooth, overlapping scales and live either on or under the ground. Five genera with about 15 species occur in the United States. A few nonnative species have been introduced into southern Florida. Missouri skinks are represented by two genera with a total of six species and one additional subspecies. All our skinks can quickly break off their tails if grasped by a predator. A new tail will regenerate, but is usually dull grayish brown.