Athyridida is an order of Paleozoic brachiopods included in the Rhynchonellata, which makes up part of the articulate brachiopods.Athyridida-Paleodb
/ref> The Athyridida are the Rostrospracea of R.C Moore, 1952,Moore, Lalcker and Fischer, 1952, Invertebrate Fossils, McGraw-Hill considered at that time to be a suborder of the

Spiriferida Spiriferida is an order of extinct articulate brachiopod fossils which are known for their long hinge-line, which is often the widest part of the shell. In some genera (e.g. '' Mucrospirifer'') it is greatly elongated, giving them a wing-like ap ...

. As with the Spiriferida, the Athyridida have outwardly directed spiral brachidia that support the lophophores on either side, but instead have non-plicate shells with rounded outlines and prominent beaks but almost no inner areas on the pedicle valve. Athyridids began early in the Silurian, reached their greatest diversity in the following Devonian, and from then declined steadily until almost becoming extinct at the end of the Permian The order rejuvenated somewhat during the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

, only to decline again until becoming extinct in the

Early Jurassic The Early Jurassic Epoch (in chronostratigraphy corresponding to the Lower Jurassic Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma&nb ...

. '' Athyris'', ''

Composita ''Composita'' is an extinct brachiopod genus that lived from the Late Devonian to the Late Permian.

'', and '' Meristella'' are representative genera. Three suborders have been defined.

References

Rhynchonellata Prehistoric brachiopods Prehistoric animal orders Brachiopod orders {{brachiopod-stub