Ostepiscians are jawed fish-like animals with paired fins, paired nostrils, scales, two-chambered hearts, and boney skeletons. They are characterized by a relatively stable pattern of cranial bones, rooted, medial insertion of mandibular muscle in lower jaw. The head and pectoral girdles are covered with large dermal bones. The eyeball is supported by a sclerotic ring of several small bones. The labyrinth in the inner ear contains large otoliths. The braincase, or neurocranium, is frequently divided into anterior and posterior sections divided by fissure. Ostepiscans have a swim bladder. They do not have fin spines, but instead support the fin with lepidotrichia (bone fin rays). They also have an operculum, which helps them breathe without having to swim. They also have a swim bladder which helps the body create a neutral balance between sinking and floating. They also are able to see in color, unlike most other fish.