Common name: Black Kingfish, Cobia


Large, moderately elongate fishes with a broad, flattened head, tiny scales, a long, low soft dorsal fin preceded by short spines unconnected by membranes, and a slightly shorter anal fin. Although Cobia resemble suckerfishes (family Echeneidae), they lack  the dorsal sucking disk. 

Cite this page as:
Martin F. Gomon & Dianne J. Bray, Cobia, RACHYCENTRIDAE in Fishes of Australia, accessed 17 Jun 2024,

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Family Taxonomy

A monotypic family found in most tropical continental waters. The Cobia is related to the dolphinfishes (family Coryphaenidae) and remoras (family Echeneidae) (Johnson 1984). Recent studies by O'Toole (2002) and Gray et al. (2009) showed that these three families form the monophyletic superfamily Echeneoidea.

Family Distribution

Found worldwide in all tropical and subtropical continental waters, except for the Eastern Pacific; pelagic, often near rocky reefs and physical structures, occasionally entering estuaries.

Often seen at surface, frequently accompanying large rays and sharks, but rarely in temperate waters.

Family Description

Meristic features: Dorsal fin VII-IX (not interconnected) + 26-33; Anal fin II-III, 22-28; Caudal fin 17; Pectoral fin 21-22; Pelvic fin I. 5; Gill rakers 2 + 9-10.
Body depth about 18% SL; head length about 24% SL. Lower jaw protruding; band of fine teeth on jaws, roof of mouth and tongue; front of soft dorsal and anal fins distinctly higher than rest of fin; pectoral fins pointed, upper rays longest; posterior margin of caudal fin concave in adults, upper lobe longer than lower, fin rounded in juveniles.

Family Size

Maximum length 2 metres; weight to 50 kg.

Family Colour

Dark brown above and on side with 2 narrow white lengthwise stripes from head to base of tail, only one dorsolaterally in large adults; white to yellowish below.

Family Feeding

Carnivore, feeding on crustaceans, squid and fish. 

Family Commercial

A popular recreational fish, caught most frequently on lures or with live fish bait. Cobia provide powerful runs and struggle violently when gaffed. The dry white flesh is of excellent quality.


Martin F. Gomon & Dianne J. Bray


Gomon, M.F. 2008. Family Rachycentridae (pp. 572). In: Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.
Gray, K.N., McDowell, J.R., Collette, B.B. & Graves, J.E. 2009. A molecular phylogeny of the remoras and their relatives. Bulletin of Marine Science 84(2): 183-198.
Johnson, G.D. 1984. Percoidei: development and relationships. 464-498 figs 254-264 in Moser, H.G. et al. (eds). Ontogeny and Systematics of Fishes. American Society of Ichthyologists and Herpetologists. Special Publication 1: 1-760.
O'Toole, B. 2002. Phylogeny of the species of the superfamily Echeneoidea (Perciformes: Carangoidei: Echeneidae, Rachycentridae, and Coryphaenidae), with an interpretation of echeneid hitchhiking behaviour. Canadian Journal of Zoology 80(4): 596-623.
Shaffer, R.V. & Nakamura, E.L. 1989. Synopsis of biological data on the cobia Rachycentron canadum (Pisces: Rachycentridae). NOAA Tech. Rep. NMFS 82. 21 pp.
Smith, M.M. 1986. Family No. 212: Rachycentridae. pp. 661-662, 1 fig. in Smith, M.M. & Heemstra, P.C. (eds). Smith's Sea Fishes. Johannesburg : Macmillan South Africa xx + 1047 pp. 144 pls