Rubyfish
species of fish
The rubyfish (Plagiogeneion rubiginosum), also known as the cosmopolitan rubyfish, red ruby or ruby rover, is a species of marine ray-finned fish, belonging to the family Emmelichthyidae, the rovers, bonnetmouths and rubyfishes. This species is found from the southeastern Atlantic Ocean off South Africa through the Indian Ocean to the southwestern Pacific Ocean around Australia and New Zealand. This species is commercially important.
Taxonomy
The rubyfish was first formally described in 1875 as Therapon rubiginosus by the English-born New Zealand geologist and biologist Frederick Hutton, with its type locality given as the coast of Otago in New Zealand. In 1890 Henry Ogg Forbes reclassified T. rubiginosus in a new monospecific genus Plagiogeneion, making this the type species of that genus. Plagiogeneion is classified within the family Emmelichthyidae in the order Acanthuriformes.
Etymology
The specific name rubiginosum means "rusty" and refers to the overall reddish colour of this fish. As Forbes's generic name Plagiogeneion is neuter, the ending of Hutton's specific name had to be altered to -um.
Description
The rubyfish has a moderately elongated body with a single continuous dorsal fin and a strongly forked caudal fin, with a highly protrusible mouth. The dorsal fin is supported by 12 or 13 spines and 10 or 11 soft rays, while the anal fin has 3 spines and 10 soft rays.
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This entry incorporates text from “Rubyfish” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.