Rhenanida
| Rhenanida | ||||||||
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Gemuendina stuertzi from the Lower Devonian Hunsrück ( Hunsrück slate ). Plaster cast of the back in the Museum für Naturkunde Berlin |
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| Temporal occurrence | ||||||||
| Lower Devon to Middle Devon | ||||||||
| 409.1 to 391.9 million years | ||||||||
| Locations | ||||||||
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| Systematics | ||||||||
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| Scientific name | ||||||||
| Rhenanida | ||||||||
| Broili , 1930 |
The Rhenanida (Rhenaniformes, Asterosteidae) are a group of the extinct Placodermi , fish-like, heavily armored vertebrates from the Devonian . They were bottom -dwelling marine animals.
features
The Rhenanida were flattened like rays. In contrast to all other placoderms, whose head and torso were armored by large bone plates, the Rhenanida had armor made of a mosaic of small bone plates. They only had one gill opening on each side. The mouth opening was on the underside of the head. The Rhenanida reached 20 to 30 centimeters in length.
There are only three well-known genera, Bolivosteus , Gemuendina, and Jagorina .
literature
- Joseph S. Nelson: Fishes of the World . John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- Robert L. Carroll: Paleontology and Evolution of the Vertebrates . Thieme, Stuttgart 1993, ISBN 3-13774-401-6 .
- John A. Long: The Rise of Fishes . The Johns Hopkins University Press, 1995, ISBN 0801849926 .
Web links
Commons : Rhenanida - collection of images, videos and audio files
- Rhenanida near Palæos
Gemuendina stuertzi . Image from the New York American Museum of Natural History