Cladoselache

Cladoselache is a genus of shark. It appeared in the Devonian period.

This primitive shark grew to be up to 1.8 metres (5.9 ft) long and roamed the oceans of North America. It is known to have been a fast-moving and fairly agile predator due to its streamlined body and deeply forked tail. Cladoselacheis one of the best known of the early sharks in part due to the well preserved fossils that were discovered in the Cleveland Shale on the south shore of Lake Erie. In addition to the skeleton, the fossils were so well preserved that they included traces of skin, muscle fibers, and internal organs, such as the kidneys.[1]