Lepisosteiformes

(formerly Lepidosteiformes), an order of freshwater fishes of the ganoid group. The fishes have a long, cylindrical body covered with an armor of strong, rhomboid ganoid scales. The olfactory sacs and the nostrils are located at the tip of the elongated snout. The spinal column is totally ossified. The vertebrae of Lepisosteiformes, unlike those of all other fishes, are opisthocoelous, that is, convex in front and concave behind.

Fossils of the order have been found in Europe in Cretaceous deposits and in North America and Asia (India) in Eocene deposits. Modern representatives comprise a single family, embracing the single genus Lepidosteus.