Stratum.black
Pentacrinites — Pentacrinites
Pentacrinites — NobuTamura email:nobu.tamura@yahoo.com www.palaeocritti.com, Wikimedia Commons, CC BY SA 3.0

Crinoid

Pentacrinites

Star-stemmed crinoid

Pentacrinites is the Jurassic crinoid with pentagonal, star-shaped stem columnals that litter the beaches of Lyme Regis and Charmouth and appear pyritised at Holzmaden. Complete crowns with arms are rare; the loose 'star stones' are cheap beach finds. Pyritised Dorset Pentacrinites decay in damp air.

PhylumEchinodermata
ClassCrinoidea
OrderIsocrinida
FamilyPentacrinitidae
GroupCrinoid
Rank (PBDB)genus· Paleobiology Database
AuthorBlumenbach 1804· Paleobiology Database
Classification (PBDB)Echinodermata › Crinoidea › Isocrinida › Pentacrinitidae· Paleobiology Database
Range (PBDB)247–33.9 Ma· Paleobiology Database
PBDB occurrences152· Paleobiology Database

Photographs

Pentacrinites — Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 69840 j)
Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 69840 j) — © The Trustees of the Natural History Museum, London, Natural History Museum (London) Data Portal, CC BY 4.0
Pentacrinites — Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 71425 (d))
Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 71425 (d)) — © The Trustees of the Natural History Museum, London, Natural History Museum (London) Data Portal, CC BY 4.0
Pentacrinites — Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 67423)
Pentacrinites fossilis Blumenbach, 1804 (NHMUK PI E 67423) — © The Trustees of the Natural History Museum, London, Natural History Museum (London) Data Portal, CC BY 4.0

Age

Formations

Elsewhere

Cite this article

Stratum Study. "Pentacrinites" (Taxon). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/taxa/pentacrinites. Accessed 2026-09-20.

BibTeX · CSL-JSON

@misc{stratum-pentacrinites,
  title        = {Pentacrinites},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/taxa/pentacrinites}},
  year         = {2026},
  note         = {Taxon article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, pbdb, wikidata, commons, nhm. 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.