Description: The Osteolepiform fish are thought to be the ancestors of the Tetrapoda due to their paired lobed fins being homologous to the limbs, and the choanae (posterior nostril). Osteolepis possessed two rounded dorsal fins placed posteriorly, and a heterocercal tail with a larger lower lobe. They have thick rhombic scales covered with a cosmine layer (hence the shine). This ancient group of fish is thought to have given rise to the Tetrapod bauplan as animals colonized the land.

Also see: Paleozoic Fish Fossils