Popular Questions for Herpetologists
What are the differences between turtles, terrapins, and tortoises?
The ocean-going chelonians (sea turtles), the freshwater species found on every warm continent, and the land-dwelling tortoises are three kinds of turtles clearly recognized as turtles by everyone. Thus, "turtle" is the generic name for all of the world's chelonians, including those called by other names such as the cooters (Pseudemys) of the southeastern United States and terrapins (Malaclemys) inhabiting brackish water along the Atlantic and Gulf coasts of North America.
Tortoises are placed in a single taxonomic family (Testudinidae) and live mostly in arid habitats, including deserts. Most tortoises have hind feet that look more like those of a miniature elephant than those of other turtles. The protective shell of nearly all species in this group is highly domed. In Australia, some of the species of side-necked turtles are referred to as "tortoises," but true tortoises in the family Testudinidae do not occur on that continent. However, the giant and bizarre horned tortoises in the extinct family Meiolaniidae that once inhabited Australia were apparently land-dwelling.
Turtles referred to as "terrapins" are found on every continent but Australia and South America and include the mangrove terrapins (Batagur affinis and B. baska) of India and SE Asia, painted terrapins (Callagur borneoensis) of SE Asia, and the Caspian and Spanish terrapins (Mauremys caspica and M. leprosa) of Africa, Europe, and Asia. In the United States a species of turtle that occupies the brackish water estuaries, tidal creeks, and salt marshes of the Atlantic and Gulf coasts from Cape Cod to Texas is known as the diamondback terrapin (Malaclemys terrapin).
In southern Florida, terrapins are found in mangrove swamps. The word "terrapin" is more American that it might appear to some people, being the name the Algonquin tribe of northeastern North America used for "edible turtle." These Native Americans used the name to refer not only to diamondback terrapins but also to other freshwater species that they consumed for food. In Malaysia, the painted terrapin, (known locally as "tuntung laut") inhabits the brackish waters of coastal areas, including mangrove swamps and river estuaries. New England whalers of the 19th century often called Galapagos tortoises "terrapins" or "turpin," a term used by Charles Darwin in his journal after going ashore on one of the islands: "Met an immense Turpin; took little notice of me." The names "turpine," "tarpain," "turupin," and "terapen" have also been found in the journals of early sailors referring to Galapagos tortoises. But no matter what the names given to all of the various species, they all qualify as "turtles."
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This information is used with permission from Johns Hopkins University Press, and is adapted from the following citation:
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