Common name: Moonfishes, Opahs



Large brightly coloured oceanic fishes with a deep body, a low long-based dorsal fin, high and pointed at the front, scythe-like pectoral and pelvic fins, and a large lunate or forked caudal fin. The lateral line is conspicuous and arches high over the pectoral fins.

Opahs are oceanic in epi- to mesopelagic depths, and are rarely seen inshore.

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Cite this page as:
Dianne J. Bray, Opahs, LAMPRIDAE in Fishes of Australia, accessed 02 Dec 2022,

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Family Taxonomy

A small family of large pelagic fishes found worldwide, with a single genus Lampris, and two species. Both species occur in Australian waters.

Family Distribution

Worldwide in tropical, temperate and cold temperate waters. One species occurs in all oceanic tropical and cool oceanic waters, and the other is only found in the Southern Hemisphere south of 30 S.

Family Size

To a fork length of more than 1.6 metres.

Family Colour

Silvery to bluish or orange to reddish in colour; one species covered in white spots.

Family Feeding

Carnivores, known to feed on krill, mesopelagic fishes and squids. A considerable amount of plastic was found in the stomachs of Lampris immaculatus in the Southern Ocean (Jackson et al. 2000).

Family Reproduction

Little is known of Lampris biology. Lampris guttatus has specialised pelagic larvae.

Family Commercial

Species are highly prized as food fish and are taken as bycatch in pelagic longline fisheries.


Dianne J. Bray


Bray, D.J. 2008. Family Lamprididae. pp. 297 in Gomon. M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp. [297]

Francis, M., L. Griggs & C.O. Maolagain. 2004. Growth rate, age at maturity, longevity and natural mortality rate of moonfish (Lampris guttatus). Final Research Report for Ministry of Fisheries Research Project TUN2003-01 Objective 1. National Institute of Water and Atmospheric Research: 1-28.

Gon, O. 1990. Lampridae. In: Gon, O. & P.C. Heemstra (eds). Fishes of the Southern Ocean. JLB Smith Institute of Ichthyology, Grahamstown, South Africa.

Hawn, D.R. & B.B. Collette. 2012. What are the maximum size and live body coloration of opah (Teleostei: Lampridae: Lampris species)? Ichthyol Res DOI 10.1007/s10228-012-0277-z

Heemstra, P.C. 1986. Lampridae. In: Smith, M.M. & P.C. Heemstra (eds). Smiths’s sea fishes. JLB Smith Institute of Ichthyology, Grahamstown, South Africa: 398 p.

Jackson, G.D., N.G. Buxton, M.J. A. George. 2000. Diet of the southern opah Lampris immaculatus on the Patagonian Shelf; the significance of the squid Moroteuthis ingens and anthropogenic plastic. Mar. Ecol. Prog. Ser. 206: 261–271.

Nelson, J.S. 2006. Fishes of the World. New Jersey : John Wiley & Sons 4th Edn 601 p.

NOAA. 2011. Fish Watch. Opah.

Olney, J.E. 1984. Lampridiformes: development and relationships, pp. 155-169, In Moser, H.G., W.J. Richards, D.M. Cohen, M.P. Fahay, A.W. Kendall, Jr, and S.L. Richardson (eds). Ontogeny and systematics of fishes. Spec. Publ. No. 1, Amer. Soc. Ichthy. Herpet., ix + 760 pp.

Olney, J.E. 1999. Lampridiformes, In Carpenter, K.E. & V.H. Niem. Species identification guide for fisheries purposes. The living marine resources of the western central Pacific. Batoid fishes, chimeras and bony fishes. Part 1 (Elopidae to Linophrynidae). FAO, Rome.

Olney, J.E., G.D. Johnson & C.C. Baldwin. 1993. Phylogeny of lampridiform fishes. Bull. Mar. Sci. 52:137-169.

Parin, N.V. & E.I. Kukuyev. 1983. Re-establishment of the validity of Lampris immaculata Gilchrist and the geographical distribution of Lampridae. Journal of Ichthyology 23(1): 1-12.

Paxton, J.R. & Gates, J.E. 2006. Family Lamprididae. pp. 536-537 in Beesley, P.L. & Wells, A. (eds). Zoological Catalogue of Australia. Volume 35 Australia : ABRS & CSIRO Publishing Parts 1-3 2178 pp. [536]

Pepperell J (2010) Fishes of the open ocean. University of Chicago Press, Chicago.

Rosenblatt, R.H. & G.D. Johnson. 1976. Anatomical considerations of pectoral swimming in opah, Lampris guttatus. Copeia 1976: 367–370.

Runcie RM, Dewar H, Hawn DR, Franck LR, Dickson KA (2009) Evidence for cranial endothermy in the opah (Lampris guttatus). J Exper Biol 212: 461–470.

Wiley, E.O., Johnson, G.D. & Dimmick, W.W. 1998. The phylogenetic relationships of lampridiform fishes (Teleostei: Acanthomorpha), based on a total-evidence analysis of morphological and molecular data. Molec. Phylogenet. Evol. 10(3): 417–425.