Lethrinus olivaceus

Lethrinus olivaceus
Conservation status
Least Concern  (IUCN 3.1) [1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Spariformes
Family:	Lethrinidae
Genus:	Lethrinus
Species:	L. olivaceus
Binomial name
Lethrinus olivaceus Valenciennes 1830
Synonyms [2]
Lethrinus longirostris Playfair, 1867 Lethrinus rostratus Valenciennes, 1830 Lethrinus rostratus specificus Borodin, 1932 Lethrinus waigiensis Valenciennes, 1830 Lethrinus xanthopterus Valenciennes, 1830

Lethrinus olivaceus, common name longface emperor or long-nosed emperor, is a species of marine ray-finned fish belonging to the family Lethrinidae, the emperors or emperor breams. This species has a wide Indo-Pacific distribution.

Taxonomy

Lethrinus olivaceus was first formally described by the French zoologist Achille Valenciennes in 1830 with its type locality given as Anyer in West Java, Indonesia. ^[3] Lethrinus longirostris has been considered to be synonymous with this species but was confirmed as a separate valid species based on morphological and genetic differences in 2022. ^[4] Some authors place the genus Lethrinus in the monotypic subfamily Lethrininae, with all the other genera of Lethrinidae placed in the Monotaxinae, however, the 5th edition of Fishes of the World does not recognise the subfamilies traditionally accepted within the family Lethrinidae as valid. The family Lethrinidae is classified by the 5th edition of Fishes of the World as belonging to the order Spariformes. ^[5]

Description

A different pattern of Lethrinus olivaceus

Lethrinus olivaceus has a body which has a standard length that is 2.8 to 3.4 times its depth with an elongated snout. In large specimens there may be a hump on the snout to the front of the eyes. ^[6] The dorsal fin is supported by 10 spines and 9 soft rays while the anal fin is supported by 3 spines and 8 soft rays. ^[2] The teeth on the jaws at the sides of the mouth are conical. The inner [[pectoral fin axilla has no scales. ^[7] The overall colour is olive grey with a scattering of irregular dark blotches on the body and sinuous dark lines on the snout. ^[8] This species has a maximum published total length of 100 cm (39 in), although 70 cm (28 in) is more typical. ^[2]

Distribution

This species is widespread in Indo-West Pacific, from Red Sea and East Africa to Samoa and Ryukyu Islands. ^{[9] [10]}

Lethrinus olivaceus from French Polynesia

Habitat

It is a reef-associated species and it can be found in lagoons, in sandy coastal areas and in reef slopes, at depths of 1 to 185 m. ^{[2] [6]}

Biology

These very active and fast swimming fishes often occur in large schools, but adults are usually solitary. They are occasionally found in small schools with Lethrinus microdon . ^[11] They feed mainly on crustaceans, cephalopods and fishes. ^[2]

Fisheries

Lethrinus olivaceus is fished for using handline fishing and fish traps, with trawling and gillnetting also being sometimes used. In New Caledonia, and possibly other regions of Oceania, this species has been found to be a cause of Ciguatera fish poisoning. ^[2]

References

1. Carpenter, K.E.; Lawrence, A. & Myers, R. (2016). "Lethrinus olivaceus". IUCN Red List of Threatened Species . 2016: e.T16720328A16722400. doi: 10.2305/IUCN.UK.2016-3.RLTS.T16720328A16722400.en .
2. Froese, Rainer; Pauly, Daniel (eds.) (2006). "Lethrinus olivaceus" in FishBase. October 2006 version.
3. Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Lethrinus". Catalog of Fishes . California Academy of Sciences . Retrieved 17 December 2023.
4. Shibuya, S.; T. Maekawa; Y. Sakurai; H. Motomura (2022). "Redescription of Lethrinus longirostris Playfair, 1867 (Perciformes: Lethrinidae), previously regarded as a junior synonym of Lethrinus olivaceus Valenciennes, 1830, on the basis of morphological and molecular evidences". Ichthy, Natural History of Fishes of Japan (in Japanese). 17: 50–66. doi:10.34583/ichthy.17.0_50. Abstract in English
5. Nelson, J.S.; Grande, T.C.; Wilson, M.V.H. (2016). Fishes of the World (5th ed.). Hoboken, NJ: John Wiley & Sons. pp. 502–506. doi:10.1002/9781119174844. ISBN   978-1-118-34233-6. LCCN   2015037522. OCLC   951899884. OL   25909650M.
6. Kent E. Carpenter; Gerald R. Allen (1989). Emperor fishes and large-eye breams of the world (Family Lethrinidae). An annotated and illustrated catalogue of lethrinid species known to date (PDF). FAO Species Catalogue. Vol. 9. FAO, Rome. pp. 77–78.
7. Kent E. Carpenter (2022). "Family Lethrinidae". In Phillip C Heemstra; Elaine Heemstra; David A Ebert; Wouter Holleman; John E Randall (eds.). Coastal Fishes of the Western Indian Ocean (PDF). Vol. 3. South African Institute for Aquatic Biodiversity. pp. 316–327. ISBN   978-1-990951-32-9.
8. Dianne J. Bray. "Lethrinus olivaceus". Fishes of Australia. MUseums Victoria. Retrieved 17 December 2023.
9. Kent E. Carpenter; Gerald R. Allen (1989). Emperor fishes and large-eye breams of the world (Family Lethrinidae). An annotated and illustrated catalogue of lethrinid species known to date (PDF). FAO Species Catalogue. Vol. 9. FAO, Rome. pp. 77–78.
10. Nicolas Bailly (2008). "Lethrinus olivaceus Valenciennes, 1830". WoRMS. World Register of Marine Species . Retrieved 17 December 2023.
11. Froese, Rainer; Pauly, Daniel (eds.) (2023). "Lethrinus microdon" in FishBase . October 2023 version.

External links

• Media related to Lethrinus olivaceus at Wikimedia Commons
• NCBI
• Animal Diversity
• Photos of Lethrinus olivaceus on Sealife Collection