See text Acentrophorus is an extinct genus of prehistoric freshwater and marine ray-finned fish from the Roadian (Guadalupian/Middle Permian) to the Wuchiapingian (Lopingian/late Permian) of England (Marl Slate), Germany (Kupferschiefer), Italy (Val Gardena) and Russia (Baitugan Formation).
[1] The type species, Acentrophorus glaphyrus, was first described under the genus name "Palaeoniscus" (=Palaeoniscum) by Louis Agassiz.
[4] Some studies suggest that Archaeolepidotus, another very early holostean, may be a junior synonym of this genus.
[5] Acentrophorus is considered to be the oldest known neopterygian,[6] the group of ray-finned fish that encompasses the vast majority of extant species.
The former species "A. chicopensis" Newberry, 1888 from the Late Triassic/Early Jurassic Portland Formation of Massachusetts is both significantly younger than other members of the genus and has differing morphology, and it is thus no longer considered to belong to the genus.