Chloroscombrus

Chloroscombrus
The Atlantic bumper, Chloroscombrus chrysurus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Suborder:	Percoidei
Superfamily:	Percoidea
Family:	Carangidae
Genus:	Chloroscombrus Girard, 1858
Type species
Micropteryx cosmopolita Agassiz, 1829
Species
Chloroscombrus chrysurus Chloroscombrus orqueta

Chloroscombrus is a genus containing two species of tropical to temperate water marine fish in the jack and horse mackerel family Carangidae. Both members are commonly known as bumpers or bumperfish, with one species endemic to the Atlantic and the other to the eastern Pacific. They have a convex ventral profile compared to most other carangids, with small oblique mouths and low dorsal and anal fins. Phylogenetic studies have found they are most closely related to the jacks of the genus Hemicaranx, with these genera plus Selar, Selaroides and possibly Alepes making up a clade within the Caranginae subfamily. They are predatory fish which live in both inshore and offshore environments ranging from estuaries to the edge of the continental shelf, and are of moderate importance to fisheries.

Taxonomy and phylogeny

Chloroscombrus is a genus containing two extant species. It is part of the jack family, Carangidae, a group of perciform fish in the suborder Percoidei.^[1] Recent phylogenetic studies using molecular information have placed Chloroscombrus in the subfamily Caranginae (or the tribe Carangini).^[2] The most recent phylogenetic study found the genus is very closely related to Hemicaranx, with the genera Selar, Selaroides and possibly Alepes also placed in a clade within the Carangini. The study also strongly supported the monophyly of Chloroscombrus^[3]

Chloroscombrus was created by the French naturalist Charles Frédéric Girard in 1858 to accommodate a 'new' species he had described; Chloroscombrus caribbaeus, making this the original type species.^[4] For some reason, probably a lack of a type specimen for C. carribaeus, David Starr Jordan and Gilbert redesignated Micropteryx cosmopolita as the type species of Chloroscombrus, which currently remains the accepted type species.^[5] However, both these names were subsequently found to be junior synonyms of Linnaeus' Scomber chrysurus, effectively making Chloroscombrus chrysrus the type species. The name is derived from the Greek words chloros; meaning green and skombros; meaning fish, particularly mackerel.^[6]

No species pertaining to Chloroscombrus are known from the fossil record, with FishBase listing only two valid extant species.^[6] There are suggestions that the two species may be conspecific, although no detailed study has been undertaken to prove such a relationship.^[7]

Species

• Genus Chloroscombrus
  • Atlantic bumper, Chloroscombrus chrysurus (Linnaeus, 1766).
  • Pacific bumper, Chloroscombrus orqueta Jordan & Gilbert, 1883.

Description

Both species of Chloroscombrus are small to medium sized fishes, growing to maximum known lengths of around 30 cm (C. orqueta)^[8] and 65 cm (C. chrysurus).^[9] The genus is easily distinguished among most of the other carangid genera, although the bigeye scad, Selar crumenophthalmus, may be confused with the Pacific member of the genus.^[10] The distinguishing features of the genus include a more convex ventral profile than the dorsal profile, giving a very rounded underside appearance, a distinct black saddle on the upper part of the caudal peduncle, a small oblique mouth and a relatively small pupil diameter.^[7][11] The rest of the general body plan of the genus is similar to other carangids, with two separate, rather low dorsal fins; the first consisting of 8 spines and the second of 1 spine and 25 to 29 soft rays. The anal fin is also low, consisting of 2 detached spines anteriorly, followed by 1 spine and 25 to 29 soft rays.^[11] The lateral line is moderately curved anteriorly, with 6 to 14 weak scutes on the straight section. The chests are completely scaled, and the jaws contain bands of fine villiform teeth.^[7] The species are silvery in colour, with the dorsal surface ranging from blue-green to dark metallic blue. C. orqueta has a distinct black spot on the upper edge of the operculum while C. chrysurus does not.^[7][11]. It is also known under local common name "plat plat".

Distribution and habitat

The two species in the genus are restricted to the tropical and temperate waters of the Atlantic and east Pacific Oceans, with C. chrysurus inhabiting both the east Americasn and west African/European coasts of the Atlantic^[11] and C. orqueta inhabiting the Central American coastline of the east Pacific.^[7]

Both species are schooling coastal species, found on the continental shelf leading pelagic lifestyles. They are commonly found in shallow water environments including beaches, lagoons and estuaries. They are also rarely found in open ocean environments, commonly associated with floating objects such as jellyfish.^[7][11]

Biology and fishery

Both species of Chloroscombrus are predatory, taking a variety of small prey including fish, cephalopods and zooplankton, with juveniles generally taking more planktonic prey than adults.^[9] Reproduction in the genus has been studied, as have the larval stages of both species, with juveniles often found in more oceanic waters.^[11]

No specific fishery exists for either species, although they are taken by trawls, seines and hook and line methods, and sold fresh, salted or frozen at market.^[7][11] Neither species are considered good gamefish, although are taken by anglers occasionally,^[10] and are considered rather dry table fishes.^[11]

References

1. ^ "Chloroscombrus". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=168669. Retrieved 29 January 2008. 
2. ^ Zhu, Shi-Hua; Zheng, Wen-Juan; Zou, Ji-Xing; Yang, Ying-Chun; Shen, Xi-Quan (2007). "Molecular phylogenetic relationship of Carangidae based on the sequences of complete mitochondrial cytochrome b gene". Acta Zoologica Sinica 53 (4): 641–650. 
3. ^ Reed, David L.; Kent E. Carpenter and Martin J. deGravelle (2002). "Molecular systematics of the Jacks (Perciformes: Carangidae) based on mitochondrial cytochrome b sequences using parsimony, likelihood, and Bayesian approaches". Molecular Phylogenetics and Evolution 23 (3): 513–524. doi:10.1016/S1055-7903(02)00036-2. PMID 12099802. 
4. ^ Girard, C.F. (1858). "Notes upon various new genera and new species of fishes, in the museum of the Smithsonian Institution, and collected in connection with the United States and Mexican boundary survey: Major William Emory, Commissioner". Proceedings of the Academy of Natural Sciences of Philadelphia 10: 167–171. 
5. ^ Jordan, D.S.; C.H. Gilbert (1883). "Synopsis of the fishes of North America". Bulletin of the United States National Museum 16 (i-iiv): 1–1018. 
6. ^ ^{a b} Froese, Rainer, and Daniel Pauly, eds. (2009). "Carangidae" in FishBase. May 2009 version.
7. ^ ^{a b c d e f g} Fischer, W.; Krupp F., Schneider W., Sommer C., Carpenter K.E. & Niem V.H. (1995). Guía FAO para la identificación de especies para los fines de la pesca. Pacífico centro-oriental. Volumen II. Vertebrados - Parte 1.. Rome: FAO. pp. 953. ISBN 92-5-303409-2. http://www.fao.org/fishery/sidp/3,1/en#Ecp. 
8. ^ Froese, Rainer, and Daniel Pauly, eds. (2009). "Chloroscombrus orqueta" in FishBase. April 2009 version.
9. ^ ^{a b} Froese, Rainer, and Daniel Pauly, eds. (2009). "Chloroscombrus chrysurus" in FishBase. April 2009 version.
10. ^ ^{a b} Mexfish (2006). "Pacific Bumperfish". Photos and Species Information for Fish Caught in Mexico. http://www.mexfish.com/fish/pbump/pbump.htm. Retrieved 2009-05-30. 
11. ^ ^{a b c d e f g h} Carpenter, K.E. (ed.) (2002). The living marine resources of the Western Central Atlantic. Volume 3: Bony fishes part 2 (Opistognathidae to Molidae), sea turtles and marine mammals. FAO Species Identification Guide for Fishery Purposes and American Society of Ichthyologists and Herpetologists Special Publication No. 5. Rome: FAO. pp. 1438. ISBN 92-5-104827-4. ftp://ftp.fao.org/docrep/fao/009/y4162e/y4162e00.pdf. 

External links

• Chloroscombrus at Encyclopedia of Life