Diamondback Terrapin
Malaclemys terrapin
A brackish-water turtle (terrapin) that typically has grey skin adorned with black spots that sometimes connect to form lines, and are unique to each individual. The shel…
How to identify
A brackish-water turtle (terrapin) that typically has grey skin adorned with black spots that sometimes connect to form lines, and are unique to each individual. The shell color varies, but is usually dark yellow, green, or brown on the carapace, with a dark yellow plastron and sides. Carapace scutes are designed with a pattern of concentric black irregular rings, like growth rings in a tree trunk. The carapace length of males can reach just over 5 inches, while females grow to over 7 inches or more. Their shells are often wider at the front than the back, and they have large webbed feet for swimming.
Range
Continuous range along the east coast from Massachusetts, around the tip of Florida, and along the Gulf of Mexico coast to Corpus Christi, Texas.
Habitat
Terrapins live near the coast in brackish water marshes that flood at high tide. They can also be found in mangrove swamps in Florida. They are often found living around different species of Spartina marsh grasses.
Variations
Skin color ranges from a dark blue-grey, to olive greenish, to pale grey, or almost white, and their black spots may be numerous or nearly absent. Carapace background color also varies, and can be dark yellow, olive, or dark brown. Plastron can be solid unmarked yellow, or have black rings within the yellow scutes. Juveniles are more distinctly patterned, while adults become more dull with age.
Similar species
The diamondback terrapin is quite unique, but could possibly be confused with the wide-ranging and variable common slider (*Trachemys scripta*), or the northern map turtle (*Graptemys geographica*).
Name and etymology
Terrapin: New Latin for turtle derived from the Algonquian word for turtle.
More illustrations
Texas Diamondback Terrapin
Northern Diamondback Terrapin
Mississippi Diamondback Terrapin
Florida East Coast Diamondback Terrapin
At a glance
Range
Continuous range along the east coast from Massachusetts, around the tip of Florida, and along the Gulf of Mexico coast to Co…
Habitat
Terrapins live near the coast in brackish water marshes that flood at high tide. They can also be found in mangrove swamps in…
Guide
Reptiles and Amphibians of North America
Range map
Approximate range. © Mapbox © OpenStreetMap