Identification
The Broad-Headed Skink, Indiana's larger skink, is less often seen than its close relative: the Five-Lined Skink, as it spends much of its time higher up in trees. Like its close relative, juvenile Broad-Headed Skinks are black with bright white-yellow stripes and a blue tail and adults are brown with faded stripes and no blue coloration. This species gets its name from the enlarged, swollen red heads that males in breeding condition develop. Broad-Headed Skinks can be quite large with adults reaching lengths of around a foot (30 cm) in length.
Though there is a similar skink in Indiana that is virtually identical in some life stages, it is first worth mentioning that many people confuse skinks with salamanders due to their similar form and shiny appearance. Though the presence of scales, claws, and eyelids is a quick way to separate these reptiles from salamanders (which are amphibians), the differences in behavior and activity pattern are also quite stark. Most people encounter skinks climbing on buildings or skittering across the forest floor, in broad daylight during the warmer months. Skinks, like many other reptiles, are sun-loving creatures that thrive in warm and dry conditions and are inactive in cool and cloudy weather. Salamanders, on the other hand, are predominantly active in spring, fall, and even winter when conditions are cool and wet. Salamanders are frequently active on cool, rainy nights during the spring but otherwise seek cover under rocks, logs, or underground. Lizards and salamanders are so different that it would not be hyperbole to say that the conditions in which one thrives, might be fatal to the other.
Five-Lined Skinks grow to only about half the size of this species making it relatively simple to identify large adult Broad-Headed Skinks. However, any individuals under eight inches (20 cm) long should be more carefully examined. Five-lined skinks have four scales, on the upper lip, between the eye and the nose while broad-headed skinks have five.
Ecology and Conservation
The Broad-Headed Skink is an inhabitant of woodland environs. This solitary species is an excellent climber and as such it leads a semi-arboreal lifestyle living in holes or crevices of trees. Their diet is comprised of mostly insects, but they have also been known to eat other reptiles. The Broad-Headed Skink prefers drier areas, and has been documented to live on the ground, under rocks, or in buildings. They seek out sunny openings, but will often move into the canopy to find gaps. They are also frequently encountered on standing dead trees (snags) and on sunny rock outcrops.
Distribution
The natural range for this species is from extreme southeastern Pennsylvania south to central Florida, west through east Kansas and northwestern Illinois, and south through east central Texas. In the Midwest, the Broad-Headed Skink is found in Ohio, Indiana, Illinois, Iowa and Missouri.
Broad-Headed Skinks are a species of mature deciduous forests and are most abundant in the unglaciated hills of south-central Indiana and in the forested ravines of west-central Indiana.
Taxonomy
The generic taxonomy of skinks is muddled and contentious. For many years, these skinks were recognized in the genus Eumeces. Schmitz et al. (2002) showed that this genus was paraphyletic, and Smith (2005) suggested using the available name Plestiodon for most North American species. No subspecies of the Broad-Headed Skink are currently recognized. These lizards belong to the family Scincidae, which is represented in Indiana by a total of three species.
Literature Cited
Conant, R. and J. T. Collins. 1998. A Field Guide to the Reptiles and Amphibians: Eastern and Central North America. Houghton Mifflin Company, New York, NY.
Minton, S. A. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science.
Schmitz, A., P. Mausfeld, and D. Embert. 2004. Molecular studies on the genus Eumeces Wiegmann, 1834: phylogenetic relationships and taxonomic implications. HAMADRYAD-MADRAS 28:73-89.
Smith, H. M. 2005. Plestiodon: a replacement name for most members of the genus Eumeces in North America. Journal of Kansas Herpetology 14:15-16.