''Dapedium'' (from el, δαπέδων , 'pavement') is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus of primitive

neopterygian Neopterygii (from Greek νέος ''neos'' 'new' and πτέρυξ ''pteryx'' 'fin') is a subclass of ray-finned fish (Actinopterygii). Neopterygii includes the Holostei and the Teleostei, of which the latter comprise the vast majority of extan ...

ray-finned fish. The first-described finding was an example of ''D. politum'', found in the Lower Lias of Lyme Regis, on the Jurassic Coast of England ( Leach 1822). ''Dapedium'' lived in the late Triassic and Jurassic periods.

Appearance

The various species of ''Dapedium'' ranged from long, and all had an oval to near-circular body. The skin was covered with thick, rhomboid, ganoid (enamel-like) scales. The smallest species so far found is ''D. noricum''. The skull was armoured with bony dermal plates, which were especially plentiful in the

orbital Orbital may refer to: Sciences Chemistry and physics * Atomic orbital * Molecular orbital * Hybrid orbital Astronomy and space flight * Orbit ** Earth orbit Medicine and physiology * Orbit (anatomy), also known as the ''orbital bone'' * Orbito ...

region. These bones bore irregular tubercles. The small pectoral and

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s, along with the extended dorsal and

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

s formed a functional unit with the tail. The tail was short and stout, providing the power for a sudden change in direction while the fish was swimming.