A fossil unicorn crestfish ( Teleostei , Lampridiformes , Lophotidae ) from the 1 Eocene of Iran

8 Lophotidae, or crestfishes, is a family of rare deep-sea teleosts characterised by an enlarged 9 horn-like crest on their forehead. They are poorly represented in the fossil record, by only 10 three described taxa. One specimen attributed to Lophotidae has been described from the 11 pelagic fauna of the middle-late Eocene Zagros Basin, Iran. Originally considered as a 12 specimen of the fossil lophotid †Protolophotus, we argue that it represents a new genus and 13 species. †Babelichthys olneyi, gen. et sp. nov., differs from the other fossil lophotids by its 14 relatively long and strongly projecting crest, suggesting a close relationship with the modern 15 unicorn crestfish, Eumecichthys. This new taxon adds to the uniqueness of the deep-sea 16 teleost fauna to which it belongs, improving our understanding of the taxonomical 17 composition of the mesopelagic ecosystems in the early Cenozoic. 18 19