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Carettochelys insculpta, Pig-nosed Turtle
Dr. Gabe S. Bever - New York Institute of Technology
Carettochelys insculpta
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Florida Museum of Natural History (UF 49415)

Image processing: Dr. Amy Balanoff
Image processing: Dr. Julian Humphries
Publication Date: 01 Mar 2004


Carettochelys insculpta is widely considered one of the most interesting and unique of the living turtles. A thick protruding snout with laterally-placed nares gives the head of C. insculpta a superficially pig-like appearance. The paddle-like forefeet are used to propel C. insculpta (much like sea turtles and unlike most other aquatic turtles, which use their hindlimbs for propulsion) through the freshwater streams, rivers, lakes, and lagoons of Papua New Guinea and the Daly, Victoria, and Alligator river drainages of the Northern Territory, Australia (Ernst and Barbour, 1989). The pig-nosed turtle, perhaps not surprisingly given its name, is known to consume a wide variety of food items ranging from fruits, seeds, roots, and leaves to snails, insects, and small fish.


Carettochelys insculpta is the sole living member of the Carettochelyidae, a group whose stratigraphic range extends as far back as the Mesozoic (Cretaceous of central Asia). Tertiary records of carettochelyids are relatively abundant and allocated to one of two primary groups, the Anosterinae and Carettochelyinae. Fossils from both groups are common in the Eocene of Asia, Europe, and North America, but only the Carettochelyinae (which includes the living C. insculpta) appears to have survived into the Miocene. Miocene-aged carettochelyine fossils are recovered from Africa, Arabia, Europe, and New Guinea.


Cladistic analyses of both morphological and molecular characters place the Carettochelyidae as a close relative to the soft-shelled turtles of the Trionychidae (Meylan, 1987; Meylan and Gaffney, 1989; Shaffer et al., 1997). Skeletal characters that diagnose carettochelyids and trionychids as a monophyletic group include fusion of the left and right premaxillae, lack of bony suturing between the carapace and plastron, strong suturing of the ribs to the vertebral centra, a relatively long coracoid process, contact between the radius and ulna adjacent to the manus, and three or fewer clawed digits.

Other skeletal characters of systematic interest that are present in C. insculpta include reduction of the vomer, anterior truncation of the palatines, lack of an external process of the pterygoid, posterior closure of the incisura columella auris, relative lack of cheek emargination, division of the pterygoids by the basisphenoid, ten or fewer peripherals, and the presence of processes extending ventrally from the nuchal.

About the Species

This specimen was collected from the Indonesian portion of New Guinea. It was made available to The University of Texas High-Resolution X-ray CT Facility for scanning courtesy of the Florida Museum of Natural History. Funding for scanning was provided by a National Science Foundation Digital Libraries Initiative grant to Dr. Timothy Rowe of The University of Texas at Austin.

About this Specimen

This specimen was scanned by Matthew Colbert on 6 November 2003 along the horizontal axis for a total of 204 1024x1024 pixel slices. Each slice is 0.5 mm thick, with an interslice spacing of 0.4 mm and a field of reconstruction of 268 mm.

About the


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Carettochelys insculpta on the Integrated Taxonomic Information System.

Carettochelys insculpta on Tortoise.org

Images and information about Carettochelys at Carettochelys.com.

The research website of Dr. Eugene Gaffney of the American Museum of Natural History

& Links

To cite this page: Dr. Gabe S. Bever, 2004, "Carettochelys insculpta" (On-line), Digital Morphology. Accessed July 12, 2024 at http://digimorph.org/specimens/Carettochelys_insculpta/.

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