Rhincodon typus

Whale shark tooth from the Pungo River Formation at Lee Creek mine.

Rhincodon typus is the world's largest living fish. Not to be confused with Paleorhincodon.

Fossil Record Edit

The whale sharks have a fossil record extending back into the Paleogene. The teeth of the modern species' design can be traced to the Oligocene (Chandler Bridge Formation) of South Carolina. During the Miocene, they are represented in the Loupian fauna of France (Cappetta, 1970) and Lee Creek (Pungo River Frm) of North Carolina. These teeth are also present in the Yorktown (Pliocene) of the later and Kent (1994) includes them in the Miocene & Pliocene (Calvert & Yorktown Frms) of Maryland and Virginia. Purdy et al (2001) noted these teeth from Pungo River (units 1 & 2) sediments but elected to identify the teeth to genus only.

Teeth Edit

The teeth are small (reaching 6 mm) with a stout (when viewed laterally) lower, and slender upper, crown. The lingual crown face is perpendicular to the basal face of the root and the labial is lingually directed. The cusp is smooth, bears a cutting-edge and its apron extends basally, down the face of the root.

The root is bilobed, labio-lingually elongated and laterally compressed. The nutrient groove is distinct, broadening labially and growing deeper lingually. A large foramen resides in posterior of the groove, and laterally, the lobe faces bear marginal foramen. The upper surface of the root has a distinct enameloid coating.

See Also Edit