Common name: Codlets, Pelagic Cods, Codlings, Unicorn Cods


A family of small tropical and subtropical pelagic fishes found from shallow inshore waters to deeper oceanic areas. They are long slender fishes with a small head and a characteristic fin pattern. All have a single long dorsal ray on the back of the head, very long pelvic-fin rays and bilobed second dorsal and anal fins. There is uncertainty regarding the number of species worldwide and the family is in need of revision.

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Dianne J. Bray, Codlets, BREGMACEROTIDAE in Fishes of Australia, accessed 13 Jul 2024,

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Family Taxonomy

A small family with a single genus and 14 described species. Six species are known from Australian waters.

Family Distribution

Pelagic or mesopelagic in tropical seas and subtropical seas worldwide. Bregmacerotids inhabit the upper layers of most tropical seas, usually in open oceanic waters, but are also found close to shore, including in estuaries, or over the continental shelf. Only gadiform family limited to warm waters.

Family Description

Small pelagic fishes with long slender bodies, a small head and relatively large eyes. The first dorsal fin is a single, long spine-like ray on the back of head. The second dorsal and anal fins are long-based with short middle rays giving the fins a bilobed appearance. The caudal fin is separate. The pelvic fins are jugular, with very long, filamentous rays. The scales are relatively large, and the lateral line is high on body, running along dorsal body margin.

Family Size

Rarely reaching 12 cm.

Family Feeding

Feed mostly on planktonic crustaceans.

Family Reproduction

The ecology and life history of bregmacerotids is poorly known. Some species reach sexual maturity by 15 mm, most by 30 mm. They spawn realtively small round pelagic eggs. Larvae are pelagic at all stages and are characterized by the distinctive early-forming dorsal ray on head, which varies in size and appearance, elongate, jugular pelvic rays and heavy internal pigment over visceral mass. Larvae are found year-round in coastal and oceanic waters between the surface and 600 m. Metamorphosis is gradual and direct.

Family Commercial

Some species are locally abundant and one is commercially harvested. There is no commmercial catch in Australian waters.

Family Conservation

Not assessed.

Family Remarks

Adults and subadults of some species undertake long vertical migrations. Although bregmacerotids are often thought of as oceanic species, about half the known species are abundant over continental shelves or in estuaries where they complete their life cycles. The adults and juveniles are most common between surface and about 300 metres, inshore species usually found closer to surface than those in open ocean.


Dianne J. Bray


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