The Common Snapping Turtle

Chelydra Serpentina by Peter Uetz

Species Description:
The common snapping turtle has a large head with a strong beak instead of teeth. The edges of the jaws have sharp edges to rip apart food. The squamosal meets the postorbital bone in the skull, but doesn't meet the parietal. The maxilla bone and quadratojugal also don't meet. The stapes is enclosed by the quadrate bone. This turtle does not have a secondary palate in the roof of the mouth. The vertebrae help create the carapace and then extend into opisthocoelous caudal vertebrae of the long tail. This long tail is armored by the dermal scales. The carapace has laterally reduced pleurals, 11 peripleurals, and long rib-like processes on the nuchal. The plastron is reduced and joined to the carapace by ligaments. The shell is covered by dermal scutes that create a horny armor on the turtle shell. This is caused by the cornification of the epidermis. The pelvis does not completely meet until the later adult stage is reached. There is a wide separation in the pubic and ischiadic symphyses. Due to the common snapping turtle being aquatic most of the time, its feet are webbed and have four or five claws on each foot.

Chelydra serpentina serpentina is the scientific name for the Common Snapping Turtle. The name was given to the turtle by Carlus Linnaeus in 1758 during the time when he first gave names to all know species of animals. The common snapping turtle lineage is as follows:

Reptile

Cryptodira

Chelydridae

Chelydra serpentina serpentina

      Missouri Conservation

The Snapping Turtle lives in all kinds of aquatic habitats from rivers and lakes to ponds and small streams. While in the water, the snapping turtle loses its aggressive behavior and becomes very shy. They will move away from people and other animals in the water, unless of course they are the prey of the turtle. They avoid encounters by being bottom dwellers in their water homes, but they do occasionally come out on shore or a log to absorb some of the heat from the sunlight. They have been seen crossing roads and entering yards while moving from one habitat to another or during their reproductive season moving to suitable nesting sites.

The snapping turtle mates from April to July, with the females laying 20-50 eggs. The female will travel to her favorite nesting site, even if it means crossing roads. The turtles come out on land to court, making them more visible in the spring. The baby turtles hatch in late summer and instinctively know to head for water. The temperature makes a difference as to how many of each gender are hatched.

The Snapping Turtle likes to walk along the bottom of the pond scavenging for food. They eat lots of vegetation such as the plants growing in the pond, but they also eat fish, snakes, crustateans, and carrion. The turtle gulps its food using the incredible suction created by its buccal cavity. He extends his neck to create the negative pressure necessary to pull his prey into the mouth and down the throat. Some turtles actually spit their prey back out, shredding it with their beak before they swallow it.


John H. Tashjian and University of California

The Snapping Turtle is considered a Cryptodira because their neck is pulled directly back into their shell. The head of a snapping turtle is too big to pull all the way into the shell so they have developed a new defensve behavior in snapping at their enemies. Their hard keratinous beak on their jaw is attached to adductor muscles that are positioned at an angle with the trochlear to create an immense force. The force is so great it can take off someone's finger if they get to close. The snapping turtle needs this speciallized muscle attachement since they do not have any temporal openings in their skull through which muscles may be attached to the jaw.

The body of the snapping turtle is covered with a carapace and plastron. The carapace is the upper shell which is a brown or black color. The belly of the turtle is protected by the much smaller, yellowish plastron. They have webbed feet with claws but short digits for walking through the mud and swimming. The legs and tail look armored due to the scales covering them since they cannot be pulled into the shell for protection. The snapping turtle can grow to shell lengths of 18 inches, but most are only 10-12 inches.

Taxonomic History:

This information can be found in Ernst,C.H. and Barbour,R.W. (1989)

          Chelydra serpentina serpentina Linneaus 1758 Species:

         Chelydra serpentina Synonyms:
         Chelydra serpentina (LINNAEUS, 1758: 199)
         Testudo serpentina LINNAEUS 1758
         Testudo serpentaria WIEDEMANN 1802 (nom. subst. pro T. serpentina L.)
         Chelydra serpentina SCHWEIGGER 1812
         Devisia mythodes OGILBY 1905

Common name: Common Snapping Turtle
         Chelydra serpentina serpentina (LINNAEUS 1758)
         Chelydra lacertina SCHWEIGGER 1812
         Testudo longicauda SHAW 1831 (nomen nudum)
         Chelydra emarginata AGASSIZ 1857
         Chelydra serpentina serpentina STEJNEGER 1914

Distribution:

S-Canada (from Nova Scotia, New Brunswick, and S-Quebec, west to SE-Alberta), USA (east of the Rocky Mountains and south to the Texas coast: North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, Texas, Minnesota, Iowa, Missouri, Arkansas, Louisiana, Wisconsin, Illinois, Michigan, Indiana, Ohio, Kentucky, Tennessee, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, Virginia, West Virginia, Maryland, Delaware, New Jersey, Pennsylvania, New York, Connecticut, Massachusetts, Vermont, New Hampshire, Maine), Mexico, Guatemala, Honduras, El Salvador ?, Nicaragua, Costa Rica, Panama, Belize ?, Colombia, Ecuador

LINKS

Please use the following links to learn more about the Common Snapping Turtle. These links will also lead you to museums that have collections of Chelydra Serpentina. Almost any museum east of the Rocky Mountains that has reptiles on display will have at least one snapping turtle.
http://herpetology.com/
http://cmgm.stanford.edu/~meisen/herp/
http://www.flmnh.ufl.edu/natsci/herpetology/turtcroclist/intro.htm
http://caribou.mi.mun.ca/patricia/3d.htm
http://eagle.cc.ukans.edu/~cnaar/khs/ksherps.html
http://www.kfwis.state.ky.us/specieschecklists/reptile_list1_1Page3.html
http://wildwnc.org/af/snappingturtle.html
http://dnr.state.il.us/lands/education/kids/TURTLE.HTM
http://www.batagur.com/turtle5.htm
http://www.flmnh.ufl.edu/natsci/herpetology/turtcroclist/default.htm
http://www.flmnh.ufl.edu/natsci/herpetology/turtcroclist/content.htm
http://www.tortoise.org/archives/snapping.html
http://coloherp.org/geo/species/spechse.html
http://www.science.mcmaster.ca/Biology/Harbour/SPECIES/TURTLE/SNAP/SNAP.HTM
http://www.gwf.org/library/wildlife/ani_snapturtle.htm
http://members.carol.net/~jmaloney/animal3.htm
http://www.ucmp.berkeley.edu/collections/otherherp.html
http://www.ucmp.berkeley.edu/collections/catalogs.html
http://www.geocities.com/Heartland/Plains/3550/snapper01.html
http://www.embl-heidelberg.de/srs5bin/cgi-bin/wgetz?-e+[Reptilia-Species:'Chelydra_SP_serpentina']

References:
Ernst,C.H. and Barbour,R.W. (1989)
Turtles of the World
Smithsonian Institution Press, Washington D.C. - London

Stejneger (1918)
Proc. Biol. Soc. Washington 31: 90, 92

Linnaeus, C. (1758)
Systema Naturae.
10th Edition: 204 pp.

Feuer, R.C. (1971)
Intergradation of the snapping turtles Chelydra serpentina (Linnaeus, 1758) and Chelydra serpentina osceola Stejneger, 1918.
Herpetologica 27: 379-384


Bellairs, Angus. (1970). The Universe Natural History Series: The Life of Reptiles, Volumes 1 and 2. Universe Books, New York, NY.

Williston, Samuel Wendell. (1914). Water Reptiles of the Past and Present. The University of Chicago Press, Chicago, IL.

Romer, Alfred Sherwood. (1956) Osteology of the Reptiles. The University of Chicago Press, Chicago, IL.

Bellairs, Angus, and Attridge, J. (1957). Reptiles. Hutchinson & Co Ltd, London.

The name that Linneaus gave the common snapping turtle is used as the scientific name. The above synonyms and geographic information come from the EMBL web page by Peter Utez.


Owl's Hill Nature Center
This page is prepared by Rebecca Lyon for Herpetology, EEB 270, Yale University, April 20, 2000.