Scythes
| Scythes | ||||||||||||
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Trachipterus trachypterus |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Trachipteridae | ||||||||||||
| Swainson , 1839 |
The scythe fish (Trachipteridae) or bandfish (not to be confused with the also named Cepolidae ) are a family of the lampriformes . The ten species, which are 1.1 to 3 meters long, live pelagically in all of the world's oceans, including the Mediterranean and the northern polar sea.
features
Scythe fish have cycloid scales or modified ctenoid scales , which can be provided with tubercles. The fish, which are silver-colored by guanine platelets in their skin, have a long dorsal fin that encompasses the entire length of their body and is constantly moving in waves with red muscle fibers . The small caudal fin consists only of the upper, fan-shaped lobe, which is directed almost at right angles upwards. One anal fin is missing. The pelvic fins have a single to ten fin rays , the pectoral fins are small and aligned horizontally. The eyes are big. A swim bladder is only rudimentary, if at all. In the course of growth, the body shape changes significantly ( allometry ). The number of vertebrae is 62 to 111. Scythe fish have no ribs , their shoulder girdle is small. The skeleton is fragile, the mineral-poor and water-rich bones are light.
Their normal swimming posture is inclined, with the head up, the longitudinal axis of the fish forms an angle of about 60 ° to the horizontal . They only lie horizontally in the water when swimming quickly. The juvenile stages of the scythes have long fin rays that serve as floating appendages. Schools of hundreds of bandfish of the genus Trachipterus were seen near Iceland .
Scythe fish are fossilized with the genus Protolophotus from the Oligocene .
Systematics
The scythes are divided into three genera:
- Genus Desmodema
- Desmodema lorum Rosenblatt & Butler, 1977 .
- Desmodema polystictum ( Ogilby , 1898) .
- Genus Trachipterus
- Trachipterus altivelis Kner, 1859 .
- Ribbon fish ( Trachipterus arcticus ) ( Brünnich , 1771) .
- Trachipterus fukuzakii Fitch, 1964 .
- Trachipterus ishikawae Jordan & Snyder, 1901 .
- Trachipterus jacksonensis (Ramsay, 1881) .
- Trachipterus trachypterus ( Gmelin , 1789) .
- Genus Zu
- To cristatus (Bonelli, 1819) .
- To elongatus Heemstra & Kannemeyer, 1984 .
literature
- Joseph S. Nelson : Fishes of the World . John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- Kurt Fiedler: Textbook of Special Zoology, Volume II, Part 2: Fish . Gustav Fischer Verlag Jena, 1991, ISBN 3-334-00339-6 .
Web links
- Scythe fish on Fishbase.org (English)