Spiriferida
| Spiriferida | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Eospirifer radiatus (Sowerby, 1835) |
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| Temporal occurrence | ||||||||||||
| Silurian to Jura | ||||||||||||
| 440 to 170 million years | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Spiriferida | ||||||||||||
| Scales , 1883 |
Spiriferida (Spiriferiden) are an extinct taxon of arm pods (Brachiopoda) with a straight, mostly long lock rim, a mostly impunctate shell and a spiral (= helicopegmate) arm structure. Together with the Protorthida , Orthida , Rhynchonellida , Atrypida , Athyridida and Terebratulida , they form the taxon Rhynchonellata , which in turn belongs to the sub-strain of the Rhynchonelliformea .
features
Its housing consists of strong biconvex flaps. A large interarea in the ventral valve is characteristic, the delthyrium is open or provided with separate deltidial plates. The spiral arm structure can be directed sideways or backwards at an angle. In the history of the earth they occur from the Silurian to the Jura . Especially in the Paleozoic, spiriferids have a good biostratigraphic guide value, at least for a rough age approach. The group was first named by Libra in 1883.
Systematics
The spiriferids are divided into five sub-taxa, which are subdivided according to the formation (stripes) of the lock process, puncturing and ribbing of the shell:
- Cyrtiacea
- Suessiacea
-
Spiriferacea
- c1: Sinus and bulge ribbed
- c2: sine and bulge not tipped
- Reticulariacea
- Spiriferinacea
literature
- Bernhard Ziegler: Introduction to Paleobiology Part 3 . ISBN 3-510-65179-0
- Treatise of Invertebrate Paleontology: H (Brachiopoda revised) 2 . ISBN 0-8137-3108-9
- Ulrich Lehmann, Gero Hillmer: Invertebrates of the past . ISBN 3-432-90653-6
