Athyris

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Athyris
Temporal range: Lower Devonian - Triassic
Scientific classification
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Genus:
Athyris

McCoy, 1844
species
  • A. concentrica(Von Buch, 1834) type = Terebratula concentrica
  • A. lamellosa(Léveillé)
  • A. vittataHall
Synonyms

Cliothyris, Spirithyris, Euthyris, Cleidothyris

Athyris is a brachiopod genus with a subequally biconvex shell that is generally wider than long and a range that extends from the Silurian into the Triassic. Athyris is the type genus for the Athyrididae, which belongs to the articulate order Athyridida. R.C. Moore (1952) gives a shorter range, from the Mid Devonian to the Lower Mississippian.

Contents

Alverezites , Bruntonites , and Meristospira are among related genera.

Reassigned species

Some species originally included in Athyris have been reassigned. [1]

Ecology and taphonomy

Composition: low Mg calcite

Entire body: yes

Adult length: 10 to < 100

Adult width: 10 to < 100

Adult height: 10 to < 100

Folds: minor

Ribbing: minor

Spines: none

Internal reinforcement: none

Locomotion: stationary

Attached: yes

Life habit: low-level epifaunal

Diet: suspension feeder

Vision: blind

References: Aberhan et al. 2004, Hendy 2009

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<i>Argyrotheca</i>

Argyrotheca is a genus of very small to minute lampshells. All species share a large pedicel opening, one ridge on the inside of the pedunculate valve, pits in a diamond pattern on the inside of both valves, and without radial ridges that end in tubercles. It occurs in depths between 6 and 1300 m. It is known since the latest Cretaceous.

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References

  1. Moore, R.C. (1965). Brachiopoda. Treatise on Invertebrate Paleontology. Part H., Volume 1 and 2. Boulder, Colorado/Lawrence, Kansas: Geological Society of America/University of Kansas Press. ISBN   0-8137-3015-5.