Types of Turtles

The Tortoise and Freshwater Turtle Specialist Group at the IUCN recently published a revised taxonomy of the world's 454 turtle species (317 species and 137 subspecies).

Turtles initially divide two sub-orders, Pleurodira and Cryptodira, defined primarily by neck characteristics.

The smaller of the two suborders, Pleurodira, or Side-necked turtles, have necks that move horizontally and are placed on the side of the shell for protection. Pleurodira divide into three families:

• Chelidae - Found in Australia and New Guinea
• Pelomedusidae - Found in Sub-Saharan Africa and Madagascar
• Podocnemidae - Found in northern South America and Madagascar

Cryptodira, or hidden neck turtles, have necks that move vertically and into the shell for protection. Eleven Cryptodira families are recognized, including two different sea turtle families:

• Carettochelyidae (Pig-nose Turtles)
• Cheloniidae - (Sea Turtles)
• Chelydridae - (Snapping Turtles)
• Dermatemydidae - (River Turtles)
• Dermochelyidae - (Leatherback Turtles)
• Emydidae - (Pond Turtles)
• Geoemydidae - (Mostly Eurasian Freshwater Turtles)
• Kinosternidae - (American Mud and Musk Turtles)
• Platysternidae - (Big-headed Turtles)
• Testudinidae - (Tortoises)
• Trionychidae - (Softshell Turtles)

North American turtles cover six of the families and fifty-five separate species. Species diversity reaches its highest in the Southeast.

Most species inhabit freshwater environments and fit into four separate families.

The Florida Softshell Turtle (Apalone ferox), pictured above and representative of the Trionychidae family, resides in a variety of Southeastern slow moving, fresh water bodies, with a preference for shallow water areas.

Females can reach a length of two feet, making them one of the largest residents in their territory. While their size immunizes them from most predation except from humans, their eggs are sought by a variety of local rodents, birds and mammals.

Because they are harvested as a food source in much of their range, population levels are dropping.

Recently the Tortoise and Freshwater Turtle Specialist Group, expressed concern "that Florida's freshwater turtles are being harvested at an unsustainable rate to supply East Asian food and medicinal markets."

Seven different Diamondback Terrapin subspecies (Malaclemys terrapin) represent the Emydidae family, although they present a variation on the Emydidae freshwater preference theme by inhabiting transition zones between the freshwater rivers and salt water oceans of the East Coast and Gulf of Mexico.

Although none of the subspecies grows larger than a foot in length, their shell appearance differs from location to location. Additionally, all of the subspecies share the physical characteristic of having a white face with dark markings.

Omnivores, their strong beak allows them to easily crack the mollusk and crustacean shells they find in their territory.

All twelve species of Map Turtles were recently listed in CITES Appendix III, meaning cross border trade in these species requires a permit.

Two snapping turtle species (family Chelydridae) swim North American waters,the Common snapping turtle (Chelydra serpentina) and the Alligator snapping turtle (Macrochelys temminckii). It's also listed on CITES Appendix III.

Adaptibility characterizes the commons snapping turtle. It's an omnivore that consumes plant and animal life in its territory. It ranges from waterways in souther Canada to waterways along the southern United States border.

Additional detailed turtle information covering types of turtles using various descriptive terms can be found by clicking on a links in the box on the right.

© 2007-2012 Patricia A. Michaels