Sclerorhynchus is an extinct genus of primitive batoidea

Batoidea

Batoidea is a superorder of cartilaginous fish commonly known as rays and skates, containing more than 500 described species in thirteen families...

n that lived in the Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

. The namesake of the Mesozoic

Mesozoic

The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 suborder Sclerorhynchoidea, it is not quite clear whether they were closer to the Rajiformes

Rajiformes

Rajiformes is one of the four orders of batoids, flattened cartilaginous fishes related to sharks.Rajiforms are distinguished by the presence of greatly enlarged pectoral fins, which reach as far forward as the sides of the head, with a generally flattened body. The undulatory pectoral fin motion...

 (skates and rays) or to the Pristiformes (sawfishes). Its fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s have been found mainly around the Mediterranean region. The related Ganopristis

Ganopristis

Ganopristis is a prehistoric genus of saw fish whose fossils are found in rocks dating from the Maastrichtian stage. Its fossils can be found in Spain and Israel.-Species:*Ganopristis hiram*Ganopristis leptodon*Ganopristis libanica...

might actually belong in Sclerorhynchus.

Sclerorhynchus was about 1 metres (3.3 ft) long, and looked somewhat like a modern sawfish, having a long snout with tooth

Tooth

Teeth are small, calcified, whitish structures found in the jaws of many vertebrates that are used to break down food. Some animals, particularly carnivores, also use teeth for hunting or for defensive purposes. The roots of teeth are embedded in the Mandible bone or the Maxillary bone and are...

-like serrations along the sides. In other respects, it looked like a flattened shark

Shark

Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....

 with enlarged, wing-like pectoral fins. It probably used these to glide over the ocean floor, propelled by its tail, weeding out shrimp

Shrimp

Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...

s, shellfish

Shellfish

Shellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some kinds are found only in freshwater...

 and flounder

Flounder

The flounder is an ocean-dwelling flatfish species that is found in coastal lagoons and estuaries of the Northern Atlantic and Pacific Oceans.-Taxonomy:There are a number of geographical and taxonomical species to which flounder belong.*Western Atlantic...

s from the sand with its long snout.