Diplurus

Diplurus is a genus of prehistoric mawsoniid coelacanth fish which lived during the Late Triassic-Early Jurassic period in North America. The fossils of this genus are common on the eastern North American Margin, being a key taxon of the Newark Supergroup, and recovered from units such as the Bull Run Formation (Norian, Virginia), Lockatong Formation (Norian, Pennsylvania), Stockton Formation (Norian, New Jersey), Solite Quarry (Norian, North Carolina-Virginia), Midland Formation (Hettangian, Virginia), East Berlin Formation (Hettangian, Connecticut), Boonton Formation (Sinemurian, New Jersey) and the Portland Formation (Hettangian-Pliensbachian, Connecticut). Three species are know, the type D. longicaudatus (Newberry, 1878), the youngest and biggest, D. newarki, (Bryant in 1934) the oldest, followed then by "D. uddeni" (Eastman), also from older rocks and considered dubious. A recent work has recovered a 3rd or 4th species, D. enigmaticus, from the Late Triassic of New Jersey, representing another small-bodied form living in sympatry with the similarly sized D. newarki. This genus ranges in size from 15 cm of D. newarki and D. enigmaticus in New Jersey to the larger 60 cm specimens of Diplurus longicaudatus found in the Connecticut River Valley, which indicates a considerable growth and likely a change in the ecological position of the genus to a possible apex predatory niche.