Terrapene carolina triunguis (Three-toed Box Turtle)

Terrapene triunguis, commonly known as the Three-toed Box Turtle, is a subspecies of the common box turtle found in the central and southern United States. It is named for the three toes on its hind limbs, distinguishing it from other box turtle species. This terrestrial turtle is known for its high-domed shell and secretive nature, often retreating into its shell when threatened.

Scientific Classification

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Family: Emydidae
Genus: Terrapene
Species: Terrapene carolina
Subspecies: Terrapene carolina triunguis

Common Names

Three-toed Box Turtle
Three-toed Land Turtle

Identification

Description

The Three-toed Box Turtle has a high-domed, olive to brown shell with faint yellow or orange markings. Its skin is usually brown or gray, sometimes featuring orange or yellow spots, particularly on the head and legs. The plastron is typically a yellowish or tan color and has a hinge, allowing the turtle to completely close its shell for protection.

Sexual Dimorphism

Males often have red or orange eyes, while females typically have brown or yellow eyes. Males also have a concave plastron, helping them mount females during mating, whereas females have a flat or slightly convex plastron. Additionally, males tend to have longer, thicker tails compared to females.

Native Origin and Distribution

Geographical Range

This species is primarily found in the central and southern United States, including Missouri, Arkansas, Louisiana, Texas, Oklahoma, and parts of Mississippi, Alabama, and Tennessee. Some populations have been introduced to other areas through the pet trade.

Preferred Habitat

The Three-toed Box Turtle prefers humid environments such as woodlands, meadows, and river valleys. It is often found near water sources like streams and ponds but spends most of its time on land. These turtles are more tolerant of drier conditions than some other box turtle subspecies, but they still require moist hiding spots to regulate their body temperature.

Behavior

Feeding Habits

This species is omnivorous, consuming a variety of foods, including insects, worms, slugs, snails, fruits, berries, mushrooms, and vegetation. Juveniles tend to eat more protein-rich foods like insects, while adults incorporate more plant matter into their diet.

Predators

Common predators include raccoons, skunks, foxes, and birds of prey. Hatchlings and juveniles are particularly vulnerable due to their small size and softer shells. Humans also pose a threat through habitat destruction and collection for the pet trade.

Reproduction

Breeding Season

Mating typically occurs in the spring and early summer, although males may attempt to breed throughout the warm months.

Reproductive Method

Females lay 2 to 8 eggs in a shallow nest dug into loose soil or leaf litter. The eggs incubate for about 70 to 90 days, with temperature influencing the hatchlings’ sex. Warmer temperatures tend to produce more females, while cooler temperatures favor males.

Conservation

Extinction Status

The Three-toed Box Turtle is classified as Vulnerable in some regions due to habitat loss and overcollection but is not currently listed as endangered.

Threats

Major threats include habitat destruction, road mortality, collection for the pet trade, and climate change, which can disrupt breeding cycles and sex ratios.

Conservation Measures

Legal protections exist in some states, restricting collection from the wild. Conservation programs focus on habitat preservation, public awareness, and breeding initiatives to maintain stable populations.

Economic Importance

This species plays a role in controlling insect and snail populations, benefiting agriculture and gardens. It is also a popular pet, although wild collection has led to population declines in some areas.

Interesting Facts

• The Three-toed Box Turtle can regenerate parts of its shell if damaged.
• It can live over 50 years in the wild, with some captive individuals exceeding 70 years.
• Unlike some other turtles, it can completely close its shell thanks to its hinged plastron.
• Some individuals have four toes on their hind limbs, but three toes remain the most common trait.
• This turtle can travel surprisingly long distances when searching for food or a mate.