Common name: Knifejaws



Knifejaws are rather deep‑bodied fishes with teeth of adults fused to form a beak similar to those of parrotfishes; scales small, finely ctenoid, covering body and head; dorsal fin continuous and elongate, but variously developed in different species; anal fin similar and opposite soft part of dorsal fin; pectoral fins of moderate size, upper rays longest, upper corner of fin pointed; ventral fins below pectoral‑fin base, spine strong.

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Cite this page as:
Martin F. Gomon & Dianne J. Bray, Knifejaws, OPLEGNATHIDAE in Fishes of Australia, accessed 21 Jun 2024,

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Family Taxonomy

The family comprises a single genus, Oplegnathus, with 7 species; a single species is found in Australian waters.

Family Distribution

Found in temperate waters of the Indo-Pacific, and is knoen from Japan, Hawaii, South America, South Africa and southern Australia.


Martin F. Gomon & Dianne J. Bray


Waite, E.R. 1900. Notes on fishes from Western Australia, and description of a new species. Records of the Australian Museum 3(7): 210-216 fig. 37