Echinoid
Phymosoma
Cretaceous echinoid
Phymosoma is the regular Cretaceous sea urchin with rows of large tubercles for its spines, found in the Texas Cretaceous (Glen Rose, Georgetown) and the Moroccan and European chalk. Texas examples are found in creek beds and road cuts and are affordable; Moroccan ones come polished and sometimes with fake spines glued on. Well-preserved tests show the apical disc and ambulacral pores.
| Phylum | Echinodermata |
|---|---|
| Class | Echinoidea |
| Order | Phymosomatoida |
| Family | Phymosomatidae |
| Group | Echinoid |
| Rank (PBDB) | genus· Paleobiology Database |
| Author | Haime 1853· Paleobiology Database |
| Classification (PBDB) | Echinodermata › Echinoidea › Calycina › Phymosomatidae· Paleobiology Database |
| Range (PBDB) | 155–23 Ma· Paleobiology Database |
| PBDB occurrences | 84· Paleobiology Database |
| Authority (WoRMS) | (Quatrefages, 1865)· WoRMS / MolluscaBase |
| Status (WoRMS) | unaccepted· WoRMS / MolluscaBase |
| Valid name (WoRMS) | Phascolosoma· WoRMS / MolluscaBase |
| Classification (WoRMS) | Animalia › Annelida › Sipuncula › Phascolosomatidae· WoRMS / MolluscaBase |
Elsewhere
- WoRMS AphiaID: 204539
- PBDB: 32977
- Wikidata: Q4300363
- PBDB taxon page
- WoRMS / MolluscaBase record
- Wikipedia: Phymosoma
- PBDB search: Phymosoma
Cite this article
Stratum Study. "Phymosoma" (Taxon). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/taxa/phymosoma. Accessed 2026-09-20.
@misc{stratum-phymosoma,
title = {Phymosoma},
author = {{Stratum Study}},
howpublished = {\url{https://stratum.black/study/taxa/phymosoma}},
year = {2026},
note = {Taxon article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, pbdb, worms, wikidata, commons. Accessed 2026-09-20.}
} 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.