Brachiopod
Atrypa
Atrypid brachiopod
Atrypa is the rounded, finely ribbed Silurian–Devonian brachiopod found worldwide and in bulk in the Waldron Shale, Silica Formation and Iowa Cedar Valley limestone, sometimes with its frilly growth lamellae preserved. It is inexpensive and abundant; specimens showing the internal spiral brachidium are prized. Its long time range makes it a poor index fossil but a great teaching one.
| Phylum | Brachiopoda |
|---|---|
| Class | Rhynchonellata |
| Order | Atrypida |
| Family | Atrypidae |
| Group | Brachiopod |
| Rank (PBDB) | genus· Paleobiology Database |
| Author | Dalman 1828· Paleobiology Database |
| Classification (PBDB) | Brachiopoda › Rhynchonellata › Atrypida › Atrypidae· Paleobiology Database |
| Range (PBDB) | 471–336 Ma· Paleobiology Database |
| PBDB occurrences | 1479· Paleobiology Database |
Elsewhere
- GBIF: 4572358
- PBDB: 29779
- Wikidata: Q1979955
- PBDB taxon page
- Wikipedia: Atrypa
- PBDB search: Atrypa
Cite this article
Stratum Strata. "Atrypa" (Taxon). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/taxa/atrypa. Accessed 2026-09-21.
@misc{stratum-atrypa,
title = {Atrypa},
author = {{Stratum Strata}},
howpublished = {\url{https://stratum.black/strata/taxa/atrypa}},
year = {2026},
note = {Taxon article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, pbdb, commons, wikidata. Accessed 2026-09-21.}
} Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.