Din ichthys

Genus of huge placoganoid fishes chiefly from the Devonian Shales of Ohio. The jaws of the largest species are two feet in length, ending in front in a strong, sharp, upturned point. Some species, as D. terrelli, had jaws constructed like a pair of shears. Little is known of any part except the head. Many plates from other parts of the body have been found, but with a few exceptions their arrangement is an unsolved problem. Din ichthys must have been one of the most formidable of the armor-clad fishes of its time, the plate covering the back of the head being in large individuals 3 to 6 inches thick. Ab. 12 species are already known, showing great differences of form. Of the few species found outside of Ohio, one occurs in Belgium.