Thornback eels
Thornback eels | ||||||||||||
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Notacanthidae | ||||||||||||
Rafinesque , 1810 |
The thorn-back eels (Notacanthidae) ( Gr .:, "Noton" = back, "akantha" = thorn) inhabit the deep sea of all oceans at a depth of 125 to 3500 meters. They pick up bristle worms and small crustaceans from the ground with their lower mouths .
features
Thornback eels have long, laterally flattened bodies. They become 20 to 60 centimeters tall. In almost all species except for Lipogenys gillii , the dorsal fin is reduced to individually standing fin spines. Some species have three spine-like fin rays in each ventral fin. The scales are relatively small with more than 50 longitudinal rows on each side of the body. The sideline is not sunk and clearly visible. The ploughshare leg is missing, the "skull base" (Basioccipitale) has a " Condylus basioccipitalis". The swim bladder has a pneumatic duct .
Very large Leptocephalus larvae were caught, which are presumably the larval stage of the thornback eels. Thorn-back eels are an old fish family, the fossil pronotacanthus known from England and Lebanon lived from the Upper Cretaceous to the Oligocene .
Systematics
There are three genera with a total of eleven species :
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Lipogenys
Goode & Bean , 1895
- Lipogenys gillii Goode & Bean , 1895
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Notacanthus Bloch , 1788
- Notacanthus abbotti Fowler , 1934
- Notacanthus bonaparte Risso , 1840
- Notacanthus chemnitzii Bloch , 1788
- Notacanthus indicus Lloyd , 1909
- Notacanthus sexspinis Richardson , 1846
- Notacanthus spinosus Garman , 1899
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Polyacanthonotus Bleeker , 1874
- Polyacanthonotus africanus ( Gilchrist & von Bonde , 1924)
- Polyacanthonotus challengeri ( Vaillant , 1888)
- Polyacanthonotus merretti Sulak, Crabtree & Hureau , 1984
- Polyacanthonotus rissoanus ( De Filippi & Verany , 1857)
literature
- Kurt Fiedler: Textbook of Special Zoology, Volume II, Part 2: Fish , Gustav Fischer Verlag, Jena, 1991, ISBN 3-334-00339-6 .
- Joseph S. Nelson : Fishes of the World , John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
Web links
- Thornback eels on Fishbase.org (English)