Carettochelyidae
The pig-nosed turtle is the only freshwater turtle with paddle-like limbs.
This family contains a single species, Carettochelys insculpta. The range is restricted to Australia and New Guinea. Preferred habitats include rivers, lagoons, and even some brackish waters.
Pig-nosed turtles reach approximately 70cm in carapace length. The carapace is olive or gray in coloration and is covered with a leathery skin. The front limbs are paddle-like and have two claws. The snout is fleshy and pig-like in anterior view, hence the common name. Diagnostic characters include a paired articulation between the eighth cervical vertebra and the nuchal bone and the shape of the quadrate bone.
The Carettochelyidae are most closely related to the Trionychidae (softshell turtles). These two families are together recognized as the Trionychoidae on the basis of several osteological characters, including opisthocoely in all but the first and last cervical vertebrae.
Although the current range is quite restricted, fossil Carettochelyids have been found in North America and Europe, and evidence suggests Asian and South American distribution as well. The oldest fossils date to the Eocene.
Ernst, C.H., and Barbour, R.W. 1989. Turtles of the World. Smithsonian Inst. Press, Washington, D.C.
Pough, F.H., Andrews, R.M., Cadle, J.E., Crump, M.L., Savitzky, A.H., and Wells, K.D. 2000. Herpetology, 2nd ed. Prentice Hall, Upper Saddle River, NJ.
Contributors
Keith Pecor (author).
Glossary
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- motile
-
having the capacity to move from one place to another.