Family: EmydidaeSub-family: Emydinae
Genus: TerrapeneSub-genera: Carolina, Ornata, Coahuila and Nelsoni
All North American box turtles belong in the Emydidae family of turtles. This large family also includes the sliders, map turtles and pond turtles from North American and Asia. Box turtles are separated from all the other turtles in this family into the genus, Terrapene. It contains 4 species, T. carolina, T. ornata and the rarely seen T. nelsoni and T. coahuila. Terrapene carolina has 6 subspecies. All box turtles have a hinge (see picture on left by D. Senneke) on their bottom shell or plastron. The box turtles most commonly kept as pets are Terrapene carolina carolina, T. c. carolina or the Common Eastern box turtle, T. c. triunguis or the Three-toed box turtle and T. c. major or the Gulf Coast box turtle. Three other box turtles in this group are rarely seen as pets because they have small ranges or are difficult to maintain. They are the Florida box turtle or T. c. bauri, T. c. mexicana and T. c. yucatana. The Western Ornate box turtle, Terrapene ornata ornata is often seen in the pet trade.
The three common T. carolina subspecies inhabit areas close to woodlands and forage on insects, worms, snails, slugs, fallen fruit and annual plants. The seeds of many plants like summer grapes, black cherries and pokeweed have a better germination percentage when they pass through the box turtle’s digestive tract. Box turtles may be an important agent for seed dispersal in the woodland ecosystem.
The subspecies of turtles that belong to Terrapene ornata are T. o. ornata or the Western Ornate and T.o. luteola or the Desert box turtle. The Ornate box turtles are the most recently evolved box turtles and have many features that make them the most terrestrial.
Western Ornate box turtles are found inhabiting open grassland and nonagricultural fields. Their ranges may have developed along side the great herds of grazing animals on the North American Prairies. Their powerful front legs and strong claws are perfectly made for tearing apart manure piles in search of dung beetles and grubs. Studies have shown their numbers are reduced when cattle are removed from the Ornate box turtle’s home ranges.
North American box turtles are listed by The Convention of International Trade in Endangered Species of Fauna and Flora (C.I.T.E.S.) as a threatened species. Permits for their export and import are required. Many states protect their native box turtles and do not allow collection. Box turtles are a long-lived species of reptiles with a low egg /clutch number, high hatchling mortality rate and ever shrinking habitat. Their survival may depend on active conservation and research into their needs and demography.
The most common box turtles found in the pet trade or along road sides and fields are the Common Eastern, Three-toed, Gulf Coast and Western Ornate box turtles. They each have a distinctive look but each subspecies seems to have individuals that are hard to identify.
Common Eastern: 4-6 inches long with a high, domed shell and a low, middorsal keel. The carapace is usually dark brown with orange or reddish blotches of various size and shape that form an attractive pattern. The plastron may or may not have dark areas around the scute margins. The skin of the turtle is brown and the males have colorful scales on the front legs. They are found from Maine to Georgia and westward to Michigan, Illinois and Tennessee.
Three-toed: 3 1/2-5 inches long with a high-dome shell. The carapace is keeled and olive brown or yellowish brown and may or may not have markings of yellow . The markings are usually thin lines or spots and dashes. The plastron may or may not have dark areas. The skin is usually brown with yellow spots and the males have reddish heads with red, orange and black on the neck and forelegs. The beaks are also colorful. They usually have three toes on the hind feet but four toes are not uncommon. This subspecies may be found as far north as Missouri and southwards to Texas and Alabama.
Gulf Coast: 5-7 inches long with a dome shell. The shell is olive brown or dark brown and there is very little marking. The back marginal scutes are often flared outward forming a slope or skirt. This adaptation may help them walk the marshy ground during the Gulf Coast’s wet season. The plastron is usually unmarked. The skin can be light or dark brown and the males have colorful necks and forelegs. They can have three toes or four toes and are found in Gulf Coast areas of Texas, Louisiana, Alabama and western Florida.
Western Ornate: 4-5 inches long with a flattened-dome shell and no central keel, although a yellow midline is not uncommon. The shell is dark brown or black with bright yellow lines that radiate to form a starburst pattern. The plastron is always marked with yellow and brown lines. The skin is dark gray and white and the head is dark brown with spots of white or yellow. The mature males obtain a greenish color on the top of the head. Ornate box turtles are found in grasslands of South Dakota through Illinois and southward to Arizona and Texas.
Florida box turtles are sometime kept as pets. They are found only in Florida and are 5 to 5 1/2 inches long and look similar in coloration to the Western Ornate. However the carapace is a high dome and the yellow star burst patterns are thinner and more numerous. There are two thick, yellow stripes on each side of the head going from the corner of the eyes towards the neck. The plastron is cream color with fine lines of brown.