Codlet Explained

Codlets are a family, Bregmacerotidae, of cod-like fishes, containing the single genus Bregmaceros found in tropical and subtropical waters throughout the world. They are very small fishes and even the largest, B. lanceolatus, reaches only 11.5cm (04.5inches) in length.

Etymology

Their scientific name is from Greek bregma meaning the top of the head, and keras meaning "horn"; this refers to their occipital ray (a spine emerging from the top of the head).

Fossil record

Fossils of Bregmaceros are found from the Eocene to the Quaternary (age range: from 37.2 to 0.0 million years ago.). They are known from various localities in Europe, North America and South America.^[1]

A potential extinct relative, Bregmacerina, is known from the Early Miocene of Russia, where it inhabited the Paratethys. It shares close similarities to Bregmaceros in the reduction of the first dorsal fin, but differs in other aspects. It remains uncertain whether it is an actual member of the Bregmacerotidae.^[2]

Species

Currently, 14 species in this genus are recognized:

• Bregmaceros arabicus D'Ancona & Cavinato, 1965
• Bregmaceros atlanticus Goode & Bean, 1886 (antenna codlet)
• Bregmaceros bathymaster D. S. Jordan & Bollman, 1890 (codlet)
• Bregmaceros cantori Milliken & Houde, 1984 (striped codlet)
• Bregmaceros cayorum Nichols, 1952
• Bregmaceros houdei Saksena & Richards, 1986 (stellate codlet)
• Bregmaceros japonicus S. Tanaka (I), 1908 (Japanese codlet)
• Bregmaceros lanceolatus S. C. Shen, 1960
• Bregmaceros mcclellandi W. Thompson, 1840 (spotted codlet, Macclelland's unicorn-cod, unicorn cod)
• Bregmaceros nectabanus Whitley, 1941 (smallscale codlet)
• Bregmaceros neonectabanus S. Masuda, Ozawa & Tabeta, 1986
• Bregmaceros pescadorus S. C. Shen, 1960
• Bregmaceros pseudolanceolatus Torii, Javonillo & Ozawa, 2004 (false lance codlet)
• Bregmaceros rarisquamosus Munro, 1950 (big-eye unicorn-cod)

References

1. http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=35703 Paleobiology Database
2. Přikryl . Tomáš . Brzobohatý . Rostislav . Gregorová . Růžena . 2016-03-01 . Diversity and distribution of fossil codlets (Teleostei, Gadiformes, Bregmacerotidae): review and commentary . Palaeobiodiversity and Palaeoenvironments . en . 96 . 1 . 13–39 . 10.1007/s12549-015-0222-z . 1867-1608.