rudderfish, common name for members of the family Kyphosidae, small-mouthed fishes of warm seas throughout the world. Also called sea chubs, rudderfishes commonly follow vessels (whence their name), scavenging on refuse. Best known is the Bermuda chub, averaging 3 to 4 lb (1.3-1.8 kg), common off the Florida coasts. Rudderfishes are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, family Kyphosidae.

The rudderfish, Centrolophus niger, is a medusafish, the only member of the genus Centrolophus found in all tropical and temperate oceans of the world, at depths of 50 to 1,000 m. Its length is from 60 to 150 cm.

The rudderfish is a moderately elongate blunt-headed fish with long low dorsal and anal fins and small pectoral and pelvic fins. The body is covered in small, soft, easily-shed scales. Its colour is a uniform dusky brown or black, and the fish is a midwater-living species.

References

• Tony Ayling & Geoffrey Cox, Collins Guide to the Sea Fishes of New Zealand, (William Collins Publishers Ltd, Auckland, New Zealand 1982) ISBN 978-0-00-216987-5