Orthotetida
| Orthotetida Temporal range: | |
|---|---|
| Xystostrophia umbraculum (Middle Devonian of Poland, family Chilidiopsidae). Looking onto the brachial (dorsal) valve; the broad interarea of the ventral valve overhangs the hinge of the shell. | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Brachiopoda |
| Class: | †Strophomenata |
| Order: | †Orthotetida Waagen, 1884 |
| Suborders | |
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The orthotetides (Orthotetida) are an extinct order of brachiopods in the class Strophomenata. Though not particularly diverse or abundant relative to strophomenides (Strophomenida) or productides (Productida), orthotetides were nevertheless the longest-lasting order of strophomenates, surviving from the Middle Ordovician (“Llanvirn”) up until the Late Permian. Externally, many orthotetides are difficult to distinguish from strophomenides. Most fundamental differences between the two orders are internal: orthotetides have more elaborate cardinal processes and a greater diversity of shell microstructure.