Stratum.black
Eldredgeops rana — Eldredgeops rana
Eldredgeops rana — Didier Descouens, Wikimedia Commons, CC BY SA 4.0

Trilobite

Eldredgeops rana

Phacops rana

Eldredgeops rana, long known as Phacops rana, is the Middle Devonian trilobite of Ohio, New York and Pennsylvania and Pennsylvania's state fossil, with a granular glabella and large compound eyes. Enrolled specimens from the Silica Formation and Penn Dixie are the classic American trilobite. Prone specimens from the shale are often flattened; three-dimensional ones from concretions are worth more.

PhylumArthropoda
ClassTrilobita
OrderPhacopida
FamilyPhacopidae
GroupTrilobite
Rank (PBDB)species· Paleobiology Database
Author(Green 1832)· Paleobiology Database
Classification (PBDB)Arthropoda › Trilobita › Phacopida › Phacopidae· Paleobiology Database
Range (PBDB)420–379 Ma· Paleobiology Database
PBDB occurrences242· Paleobiology Database

Photographs

Eldredgeops rana — Eldredgeops rana
Eldredgeops rana — Smithsonian Institution (NMNHPALEO), Smithsonian Open Access, CC0

Age

Formations

Elsewhere

Cite this article

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

BibTeX · CSL-JSON

@misc{stratum-eldredgeops-rana,
  title        = {Eldredgeops rana},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/taxa/eldredgeops-rana}},
  year         = {2026},
  note         = {Taxon article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, pbdb, wikidata, commons, smithsonian. Accessed 2026-09-20.}
}

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