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.

Rubyfish
specimen from Sydney Fish Market
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acanthuriformes
Family: Emmelichthyidae
Genus: Plagiogeneion
Species:
P. rubiginosum
Binomial name
Plagiogeneion rubiginosum
(F. W. Hutton, 1875)
Synonyms
  • Therapon rubiginosus F. W. Hutton, 1875

Taxonomy

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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.[2] In 1890 Henry Ogg Forbes reclassified T. rubiginosus in a new monospecific genus Plagiogeneion making this species the type species of that genus.[3] Plagiogeneion is classified withion the family Emmelichthyidae in the order Acanthuriformes.[4]

Etymology

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The specific name rubiginosum means "rusty" and refers to the overall reddish colour of this fish.[5] As Forbes's generic name Plagiogeneion is neuter the ending of Hutton's specific name had to be altered to -um.[6]

Description

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The rubyfish has a moderately elongated body with a single continuous dorsal fin and a strongly forked caudal fin, with a highly protrusible mouth.[7] 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. The body has a depth of between 27% and 34% of the standard length.[8] The head and upper body are red with a silvery lower body[9] and blackish tips to the caudal fin. This species reaches a maximum published total length of 60 cm (24 in).[10]

Distribution and habitat

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The rubyfish is found in the southeastern Atlantic over the Vema Seamount to the west of Cape Town, and Walvis Bay in Namibia. In the Indian Ocean it is found off Algoa Bay in the Eastern Cape, around Île Saint-Paul and Île Amsterdam and east to southern Australia and New Zealand.[10] In Australia its range extends from West of Bunbury, Western Australia, along the tempareate southern coast to Cape Byron, New South Wales, including Tasmania.[8] It is a bathydemersal fish found at depths of from 50 to 600 m (160 to 1,970 ft), near sand or mud bottoms, typically in the vicinity of the edge of the continental shelf and around seamounts. The juveniles are epipelagic and as they mature the descend into deeper waters.[8]

Biology

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The rubyfish spawns in late spring up to early summer. It is a long lived species which has been estimated to reach 85 years of age.[11] The adults prey on larger zooplankton caught near the bottom.[8]

Fisheries

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Rubyfish is an important species for major fisheries in New Zealand and the South Pacific. In some area, this species is fished for over deep sea seamounts.[1] The catch is sold fresh or as frozen fish and it is reputed to be highly palatable.[10]

References

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  1. ^ a b Al Abdali, F.S.H.; Al Buwaiqi, B.; Al Kindi, A.S.M.; et al. (2019). "Plagiogeneion rubiginosum". IUCN Red List of Threatened Species. 2019: e.T123426979A123494667. doi:10.2305/IUCN.UK.2019-2.RLTS.T123426979A123494667.en. Retrieved 13 April 2023.
  2. ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Plagiogeneion". Catalog of Fishes. California Academy of Sciences. Retrieved 14 April 2023.
  3. ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Emmelichthyidae". Catalog of Fishes. California Academy of Sciences. Retrieved 14 April 2023.
  4. ^ J. S. Nelson; T. C. Grande; M. V. H. Wilson (2016). Fishes of the World (5th ed.). Wiley. pp. 497–502. ISBN 978-1-118-34233-6.
  5. ^ Christopher Scharpf & Kenneth J. Lazara, eds. (9 March 2023). "Series Eupercaria (Incertae sedis): Families Callanthidae, Centrogenyidae, Dinopercidae, Emmelichthyidae, Malacanthidae, Monodactylidae, Moronidae, Parascorpididae, Sciaenidae and Sillagidae". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf and Kenneth J. Lazara. Retrieved 12 April 2023.
  6. ^ N. V. Parin (1991). "Three new species of the bentho-pelagic fish genus Plagiogeneion from the southern Pacific and Indian oceans (Teleostei: Emmelichthyidae)". Proceedings of the Biological Society of Washington. 104 (3): 459–467.
  7. ^ Mark McGrouther (22 February 2021). "Cosmopolitan Rubyfish, Plagiogeneion rubiginosum (Hutton, 1875)". Australian Museum. Retrieved 14 April 2023.
  8. ^ a b c d Bray, D.J. (2020). "Plagiogeneion rubiginosum". Fishes of Australia. Museums Victoria. Retrieved 14 April 2023.
  9. ^ Philip C. Heemstra (2022). "Family Emmelichthyidae, Rovers". In P.C. Heemstra; et al. (eds.). Coastal fishes of the western Indian Ocean. Volume 4 (PDF). South African Institute for Aquatic Biodiversity. pp. 25–28. ISBN 978-1-990951-31-2.
  10. ^ a b c Froese, Rainer; Pauly, Daniel (eds.). "Plagiogeneion rubiginosum". FishBase. February 2023 version.
  11. ^ McMillan, P.J.; Francis, M.P.; James, G.D.; et al. (2011). New Zealand fishes. Volume 1: A field guide to common species caught by bottom and midwater fishing. New Zealand Aquatic Environment and Biodiversity Report. Vol. 68. Ministry of Fisheries, Wellington. p. 227. ISSN 1176-9440.
  • Tony Ayling & Geoffrey Cox, Collins Guide to the Sea Fishes of New Zealand, (William Collins Publishers Ltd, Auckland, New Zealand 1982) ISBN 0-00-216987-8