Cladodont

Cladodont (from Latin cladus, meaning branch and Greek Odon, meaning tooth) is the term for a common category of early Devonian shark known primarily for its "multi-cusped" tooth consisting of one long blade surrounded by many short, fork-like tines, designed to catch food that was swallowed whole, instead of being used to saw off chunks of meat like many modern sharks.

The earliest known shark, Cladoselache, was a cladodont existing about 370 million years ago.

[2] It had the typical cladodont teeth, which probably also were not regularly replaced like those of modern sharks, but did appear to wear down from use.

Also a cladodont, it survived from the late Devonian to the early Carboniferous, dying out about 320 million years ago.

While the earliest known sharks are cladodont, there is some evidence that they evolved from a common ancestor with "diplodonts", sharks whose teeth have two larger blades poking out, plus a small middle tine that could have become the main blade in cladodont teeth.

This is a typical Cladodont tooth, of a shark called Glikmanius
The fossil tooth of Cladodus belifer , which lived about 260,000,000 years ago in what would someday be Illinois . The roundness of the main tooth, and the small tines around it, show it to be a cladodont.