Dapediidae

Dapediidae is an extinct family of neopterygian ray-finned fish that lived from the Middle Triassic to Late Jurassic (Ladinian to Tithonian).^[2] 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, and subsequently to the separate order Dapediiformes in 2016.^[3]

Dapediidae Temporal range: Ladinian–Tithonian PreꞒ Ꞓ O S D C P T J K Pg N
Fossil specimen of Dapedium politum
Artist's reconstruction of Sargodon
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Infraclass:	Holostei (?)
Order:	†Dapediiformes Thies & Waschkewitz, 2016
Family:	†Dapediidae Lehman, 1966
Genera
†Aetheolepis †Ameghinichthys[1] †Dandya †Dapedium †Hemicalypterus †Heterostrophus †Paradapedium †Sargodon †Scopulipiscis †Tetragonolepis

Description

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.^[4] Their teeth were adapted towards a durophagous diet; some dapediids fed on hard-shelled invertebrates,^[5] while at least one genus (Hemicalypterus) may have been herbivorous.^[6]

Classification

Dapediids are usually considered to be either basal ginglymodians^[3][6] or stem group representatives of the wider clade Holostei,^[4][7] but some studies have found them to be early-diverging stem-teleosts instead.^[4]