Turtles come in many different species, each with unique characteristics for identification. Determining the specific type of turtle you have can be done by looking at physical features, behavior, habitat, and distribution. This article provides tips on identifying common pet turtle species and wild turtles found in the United States.
Pet turtle identification
The most common types of pet turtles include:
- Red-eared slider
- Painted turtle
- Box turtle
- Russian tortoise
- Greek tortoise
Use this guide to help identify your pet turtle:
| Species | Physical Features |
|---|---|
| Red-eared slider | Greenish shell, red stripes on head and legs, red or orange patch behind eyes |
| Painted turtle | Olive to black shell with red and yellow markings, red and yellow stripes on legs, feet, head |
| Box turtle | High-domed, brown or black shell, yellow, red, orange markings, orange, yellow skin |
| Russian tortoise | Elongated brown or tan shell, large scale-like scutes on shell, stubby elephant-like feet |
| Greek tortoise | Rounded, black and yellow shell, elephant-like feet, conical scutes on shell |
In addition to physical characteristics, behavior and habitat preferences can aid identification:
- Red-eared sliders bask frequently and are strong swimmers
- Painted turtles prefer slow-moving water and are timid
- Box turtles live on land and can completely enclose themselves in their shell
- Russian tortoises dig burrows and are very heat tolerant
- Greek tortoises are shy grazers that thrive in hot, arid climates
Wild turtle identification
The species of wild turtles found depends on your geographic location. Here are some of the most common wild turtles in the United States:
| Species | Geographic Range |
|---|---|
| Snapping turtle | Throughout eastern and central US |
| Western pond turtle | West coast from Baja to British Columbia |
| Eastern box turtle | Eastern US from Maine to Florida |
| Painted turtle | Canada and Eastern US |
| Slider turtle | Southeastern US |
| Gopher tortoise | Southeastern coastal US |
| Desert tortoise | Southwestern US |
Use this visual identification guide for common wild turtle species in the US:
| Species | Identifying Features |
|---|---|
| Snapping turtle | Very large (up to 19 inches), brown, jagged shell; long saw-toothed tail; long neck and small head |
| Western pond turtle | Olive green to brown shell; yellow stripes on head, neck, legs; webbed feet |
| Eastern box turtle | Domed, hinged brown or black shell; orange, red, yellow spots; orange head/neck |
| Painted turtle | Smooth black/green shell with red and yellow stripes; red markings on shell, skin, legs |
| Slider turtle | Olive green shell; yellow stripes on legs, neck; red markings behind eyes |
| Gopher tortoise | Brown, oval upper shell; flattened, shovel-like feet; stumpy, elephant-like hind legs |
| Desert tortoise | Round, bumpy brown upper shell; flat, elephantine hind feet; stocky forelegs |
Turtle shell patterns
The shape and structural patterns of a turtle’s shell can also help indicate species. Here are some key shell features to look for:
- Scutes – The larger plates that make up the shell. The number and arrangement of scutes is unique to different species.
- Marginals – The row of small scutes along the outer edge of the upper shell.
- Vertebral scutes – The row of scutes down the center of the carapace (upper shell).
- Pleural scutes – Paired scutes on either side of the vertebral scutes.
- Costal scutes – The scutes that connect the vertebral and marginal scutes.
For example, box turtles have a single hinge on their underside shell while tortoises have no hinge. Painted turtles have relatively smooth shells while gopher tortoises have rough, bumpy shells. Examining the scute patterns and shell structure can yield important clues for identification.
Turtle gender differences
Males and females of some turtle species exhibit distinct physical and behavioral differences:
- Male red-eared sliders tend to have longer front claws and tails.
- Male box turtles usually have red or orange eyes while females have brown or yellow.
- Male desert tortoises are generally larger with a more domed shell compared to females.
- During breeding season, male softshell turtles develop white or pink tubercles around the edge of the shell.
- Male musk turtles produce a distinct musky odor, especially evident when handled.
So when identifying turtle gender, look for differences in size, shell shape, eye color, claws/tail, physical markings, and behavior.
Turtle age identification
A turtle’s age can often be estimated by size and other physical attributes:
- Hatchlings have soft, leathery shells and are very small, usually less than 2 inches.
- Juveniles grow rapidly so have clean, smooth shells that show consistent growth rings.
- Mature adults slow their growth rate so shells have more weathering and prominent growth rings.
- Old turtles tend to be large in size with very worn, battered shells.
- In mature adults, the plastron (bottom shell) is concave in males and flat in females.
As they get older, turtle shells accumulate scratches, pits, algae, and other signs of aging. The relative smoothness and concavity of the shell can help indicate a turtle’s age and maturity.
Turtle identification resources
For further help identifying an unknown turtle, some useful resources include:
- Region-specific turtle field guides
- Online databases such as The Reptile Database
- Herpetological societies such as Partners in Amphibian and Reptile Conservation
- Nature centers, zoos, museums, and universities with herpetology experts
- Turtle rescue/rehabilitation organizations
- Herpetology forums and groups on social media
When posting on forums or social media, include clear, well-lit photos of the whole turtle, top and bottom shell, head, and other distinctive markings. This will help the turtle experts narrow down possibilities for species identification.
Conclusion
Identifying turtles takes practice, but close examination of physical features like the shell, skin markings, and anatomy provides key clues. Also consider the turtle’s habitat, behavior, age, gender, and geographic location. Consult field guides and turtle experts as needed for tricky identifications. With some sleuthing and deductive reasoning, you can successfully crack the case of mysterious turtle species in the wild and captivity.
