Missouri's largest forest-dwelling skink. It is a large, smooth-scaled lizard with a large, wide head. Color varies with sex and age. Adult males are usually olive brown with few or no stripes along the side, but during breeding season they develop an orange-red swollen head. Adult females nearly always have light and dark stripes down the back and sides, with a wide, dark stripe down each side being particularly prominent. Hatchlings are jet black with five narrow yellow lines along the back and sides, with a bright blue tail.
Similar species: Five-lined skinks are very similar, but they have two postlabial scales (positioned, one on top of the other, in the space between the lip scales and the ear hole); postlabial scales are usually absent or only single on the broad-headed skink.