Tylosurus acus (keel-jawed needlefish) is a game fish of the family Belonidae.
Distribution The keel-jawed needlefish is widespread in the Atlantic and Indo-Pacific oceans.
Taxonomy There are four recognised subspecies of Tylosurus acus:
T. a. acus (Lacepède, 1803) (Agujon needlefish) - in the western Atlantic from Massachusetts to Brazil and in the eastern Atlantic off Morocco and in the western Mediterranean T. a. imperialis (Rafinesque, 1810) in the Mediterranean Sea and Cape Verde Islands T. a. rafale Collette and Parin 1970 (Atlantic agujon needlefish) Gulf of Guinea T. a melanotus (Bleeker, 1850) (Keel-jawed needlefish) in the Indo-West Pacific and oceanic islands in the eastern tropical Pacific Revillagigedo Islands, Clipperton Island, and Cocos Island.
Tylosurus pacificus was once considered a subspecies of T. acus but is now considered a distinct species.Collette, B. B. and H. M. Banford 2001. Status of the eastern Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876) (Beloniformes: Belonidae). Revista de Biología Tropical v. 49 (Suppl. 1): 51-57. Although acus was suppressed by ICZN Opinion 900, continued usage of the name led to Tylosurus acus being reinstated as a valid name.Collette, B. B. 1970. Three specific names in the family Belonidae (Pisces): suppressed under the plenary powers. Bulletin of Zoological Nomenclature v. 26 (no. 5-6): 213-216.OPINION 2169 (Case 3297) Sphyraena acus Lacépède, 1803 (currently Tylosurus acus; Teleostei, BELONIDAE): reinstated as a valid name. Bulletin of Zoological Nomenclature 2007 64:75-76. Some authorities raise the four subspecies to species level.
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