 Although the first fossils of hybodonts are from the Carboniferous, they likely branched off from neoselachians (modern sharks) during the early Devonian.The group now called Hybodontiformes includes many species, with examples such as "Hybodus", "Acrodus", "Asteracanthus", "Lonchidion", and "Lissodus".Hybodont samples have been recovered from Permian deposits from Oman, indicating that hybodonts lived in the Neotethys Ocean during the Permian Period.