Dapediidae is an extinct family of neopterygian ray-finned fish that lived from the Middle Triassic to Late Jurassic (Ladinian to Tithonian).[1] It is the only family of the order Dapediiformes. Its members were historically placed within the ginglymodian family Semionotidae, but were moved to their own family in 1966.[2]
Dapediids had deep, laterally flattened circular bodies covered in thick ganoid scales, which gave them a resemblance to the pycnodontiforms, a group they may or may not be related to.[3] Their teeth were adapted towards a durophagous diet; some dapediids fed on hard-shelled invertebrates,[4] while at least one genus (Hemicalypterus) may have been herbivorous.[5]
Dapediids are usually considered to be either basal ginglymodians[2][5] or stem group representatives of the wider clade Holostei,[3][6] but some studies have found them to be early-diverging stem-teleosts instead.[3]