Strophomenids
| Strophomenids | ||||||||||
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Leptaena depressa a strophomenide from the Silurian mountains of Gotland (Sweden) |
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| Temporal occurrence | ||||||||||
| Ordovician to Devon | ||||||||||
| 480 to 360 million years | ||||||||||
| Locations | ||||||||||
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Strophomenida | ||||||||||
| Newell , 1965 |
Strophomeniden (Strophomenida) are an extinct taxon of arm pods (Brachiopoda) with usually relatively long and straight lock rim and a pseudo-punctate shell without spines. Together with the Billingsellida , Orthotetida and Productida, they form the taxon Strophomenata , which in turn belongs to the sub- strain of the Rhynchonelliformea .
features
The arm structure is missing or consists of brachiophores. Lock teeth are usually present, but in some cases functionally replaced by a series of denticles along the edge of the lock. In geological history they appear from the Ordovician to Carboniferous (as "living fossils" of the Mesozoic Era, possibly up to the Jurassic ). In some groups, their housing is attached to the shell on the ground. Their housing almost always consists of a concave and a convex (rarely a biconvex) valve. The group was first named by Öpik in 1934.
Systematics
The strophomenides are divided into two sub-taxa, the strophomenoidea and the plectambonitoidea , which are listed below with their subordinate systematic units:
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
