Promicroceras — Promicroceras
Promicroceras Ammojoe, Wikimedia Commons, CC BY SA 3.0

Ammonoid

Promicroceras

Charmouth ammonite

Promicroceras planicosta is the small, chunky-ribbed ammonite of the Charmouth Mudstone found pyritised or in limestone blocks with dozens together, the iconic Charmouth beach fossil. Pyritised examples are golden, cheap and prone to pyrite decay, so keep them dry. Limestone blocks with clustered Promicroceras and Arnioceras are sold prepared from the beach.

PhylumMollusca
ClassCephalopoda
OrderAmmonitida
FamilyEoderoceratidae
GroupAmmonoid
Rank (PBDB)genus· Paleobiology Database
AuthorSpath 1925· Paleobiology Database
Classification (PBDB)Mollusca › Cephalopoda › Ammonitida › Eoderoceratidae· Paleobiology Database
Range (PBDB)200–184 Ma· Paleobiology Database
PBDB occurrences15· Paleobiology Database

Elsewhere

Cite this article

Stratum Strata. "Promicroceras" (Taxon). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/taxa/promicroceras. Accessed 2026-09-21.

@misc{stratum-promicroceras,
  title        = {Promicroceras},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/taxa/promicroceras}},
  year         = {2026},
  note         = {Taxon article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, pbdb, wikidata, commons, smithsonian, nhm. Accessed 2026-09-21.}
}

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