Cyema atrum
Cyema atrum | ||||||||||||
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![]() Cyema atrum |
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Systematics | ||||||||||||
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Scientific name of the family | ||||||||||||
Cyematidae | ||||||||||||
Regan , 1912 | ||||||||||||
Scientific name of the genus | ||||||||||||
Cyema | ||||||||||||
Günther , 1878 | ||||||||||||
Scientific name of the species | ||||||||||||
Cyema atrum | ||||||||||||
Günther, 1878 |
Cyema atrum is a little researched fish species from the order of the eel-like (Anguilliformes). It occurs worldwide in all oceans at depths of 330 to 5100 meters.
features
Cyema atrum has a blackish, laterally flattened body that is relatively short for eels and whose shape is compared to that of a dart . The fish are 13 to 15 cm long. The dorsal and anal fins are symmetrically opposite each other, begin above or below the middle of the body, become increasingly higher towards the rear and protrude with their extended tips over the caudal fin. This consists of only a few short fin rays . The small gill openings are far down on the body below the small pectoral fins. The narrow, beak-shaped jaws are like those of the Schnepfenealen (Nemichthyidae) arched apart and cannot be closed. Both are studded with tightly packed, tiny, backward-curved teeth, which are usually arranged in the shape of a quincunx .
Systematics
The species and genus were described in 1878 by the German zoologist Albert Günther . The two type specimens were caught during the Challenger expedition . The American ichthyologist Charles Tate Regan introduced the initially monotypical family Cyematidae for the genus in 1912, to which the species Neocyema erythrosoma was assigned in 1978 . A DNA comparison of an adult specimen of Neocyema erythrosoma caught southeast of Greenland and a leptocephalus found in the Sargasso Sea with Cyema atrum and other deep-sea eels showed no closer relationship between the two species. Erythrosoma Neocyema is the sister group to a common clade of Pelikanaals (Eurypharyngidae) with the bag mouths (Saccopharyngidae) while Cyema atrum a clade with the Einkieferaalen forms (Monognathidae). The Neocyematidae family was then introduced for Neocyema erythrosoma . The family Cyematidae is again monotypical.
Individual evidence
- ^ William N. Eschmeyer, Earl S. Herald , Howard Hamann: A field guide to Pacific Coast Fishes of North America. From the Gulf of Alaska to Baja California (Peterson Field Guides; 28). Houghton Mifflin, Boston, Mass. 1983, ISBN 0-395-33188-9 . Page 68.
- ↑ Ethelwynn Trewavas : On the Structure of two Oceanic Fishes, Cyema atrum Günther and Opisthoproctus soleatus Vaillant. Proceedings of the Zoological Society of London , September 1933, doi: 10.1111 / j.1096-3642.1933.tb01609.x
- ↑ Poulsen JY, Miller MJ, Sado T, Hanel R, Tsukamoto K, Miya M (2018): Resolving deep-sea pelagic saccopharyngiform eel mysteries: Identification of Neocyema and Monognathidae leptocephali and establishment of a new fish family "Neocyematidae" based on larvae , adults and mitogenomic gene orders. PLoS ONE 13 (7): e0199982. doi: 10.1371 / journal.pone.0199982
Web links
- Cyema atrum on Fishbase.org (English)