Fossils were discovered in 2012 from construction site in Goshoura, Amakusa.[2] This site is later considered to belong to Hinoshima Formation of the Himenoura Group.[1] It was the first discovery of marine ichthyodectform fish described from Asia in detail, while other ichthyodectiform fish from Asia (three genera belong to Chuhsiungichthyidae) are from non-marine environment.[1][2]
Description
Amakusaichthys is relatively small ichthyodectiform with length around 60 cm (24 in). It is characterized by its long snout and small mouth and teeth.[1] Multiple specimens are found overlapped in one place, suggesting its schooling ecology.[2][3]
Classification
Amakusaichthys was not assigned to any family in original description. However, characters suggested that it was related to Heckelichthys.[1] In 2021, it was assigned to Bardackichthyidae, alongside Heckelichthys and Bardackichthys.[4]