Rhadinichthyidae
| Rhadinichthyidae | ||||||||||||
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Fossil of Cyranorhis bergeraci in the Smithsonian National Museum of Natural History |
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| Temporal occurrence | ||||||||||||
| Upper Devonian to Pennsylvania (Upper Carboniferous) | ||||||||||||
| Locations | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Rhadinichthyidae | ||||||||||||
| Romer , 1945 |
The Rhadinichthyidae are an extinct bony fish family from the Upper Devonian and Carboniferous .
features
The Rhadinichthyidae are small, somewhat stocky or slender fish and in many cases only reached a body length of just over ten centimeters or remained below. They have a protruding snout and a slightly below muzzle. The premaxillary is missing, resulting in a notch on the top of the snout. The opercular is taller but shorter than the subopercular. The melting flakes are square and arranged in diagonal rows.
The pectoral fins are narrow, the pelvic fins very small. The dorsal fin is triangular and stands behind the center of the body, just before the anal fin or directly opposite. The caudal fin is heterocerk and deeply split. Your two praises are of unequal length, but in Cyranorhis the same length. In all fins the fin rays are divided into two distally .
Systematics
The Rhadinichthyidae are assigned to the order Palaeonisciformes by Nelson , a heterogeneous group of primitive chondrostei . Richard Lund & Cécile Poplin assign them, without family or order, as the most basal taxon after Cheirolepis, directly to the ray fins (Actinopterygii).
Genera
- Aetheretmon White, 1927
- Cycloptychius Young, 1966
- Cyranorhis Lund & Poplin, 1997
- Eigilia Kazantseva, 1981
- Ganolepis Woodward, 1893
- Eurylepidoides Case, 1935
- Illinois Schultze & Bardack, 1987
- Mentzichthys Jubb, 1965
- Nozamichthys Schultze & Bardack, 1987
- Rhadinoniscus White, 1937
- Rhadinichthys Traquair, 1877
- Strepheoschema White, 1927
- Uydenia Kazantseva-Selezneva, 1980
- Wendyichthys Lund & Poplin, 1997
literature
- Karl Albert Frickhinger: Fossil Atlas of Fishes. Mergus, Verlag für Natur- und Heimtierkunde Baensch, Melle 1999, ISBN 3-88244-018-X .
- Richard Lund, Cécile Poplin: The rhadinichthyids (paleoniscoid actinopterygians) from the Bear Gulch Limestone of Montana (USA, Lower Carboniferous). In: Journal of Vertebrate Paleontology. Volume 17, Issue 3, 1997, ZDB -ID 2173776-9 , pp. 466-486, doi : 10.1080 / 02724634.1997.10010996 .
- Joseph S. Nelson : Fishes of the World. 4th edition. John Wiley & Sons, Hoboken NJ 2006, ISBN 0-471-25031-7 .
Web links
- The Paleobiology Database: Rhadinichthyidae
- Permo Triassic Fishes: Rhadinichthyidae