Odontodes

Odontodes, or dermal teeth, are hard structures found on the external surfaces of animals or near internal openings. They consist of a soft pulp surrounded by dentine and covered by a mineralized substance such as enamel, a structure similar to that of teeth. They generally do not have the same function as teeth, and are not replaced the same way teeth are in most fish. In some animals (notably catfish), the presence or size of odontodes can be used in determining the sex.

The name comes from the Greek "odon" meaning tooth.

A New Species of Hisonotus (Siluriformes, Loricariidae) of the Upper Rı´o Uruguay Basin (see page 7) An article showing scanning electron microscope images of odontodes on a catfish. Author:Adriana E. Aquino, Scott A. Schaefer, Amalia M. Miquelarena. Publisher: The American Museum of Natural History.

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