Stratum.black
Diplomystus dentatus — Diplomystus dentatus Cope
Diplomystus dentatus Cope — Smithsonian Institution (NMNHPALEO), Smithsonian Open Access, CC0

Fish

Diplomystus dentatus

Double-hinged herring

Diplomystus dentatus is the deep-bodied Green River herring relative with an upturned mouth and a row of dorsal scutes, the second-commonest Fossil Lake fish after Knightia. Large specimens (30 cm and up) and 'aspiration' plates with a Diplomystus choking on a Knightia are collector favourites. Preparation quality varies enormously between the 18-inch layer and the split-fish layer.

PhylumChordata
ClassActinopterygii
OrderEllimmichthyiformes
FamilyParaclupeidae
GroupFish
Sizeto 65 cm; usually 10–30 cm
Rank (PBDB)genus· Paleobiology Database
AuthorCope 1877· Paleobiology Database
Classification (PBDB)Chordata › Osteichthyes › Ellimmichthyiformes › Armigatidae· Paleobiology Database
Range (PBDB)143–33.9 Ma· Paleobiology Database
PBDB occurrences25· Paleobiology Database

Photographs

Diplomystus dentatus — Diplomystus dentatus Cope, 1877 (NHMUK PV P 52516)
Diplomystus dentatus Cope, 1877 (NHMUK PV P 52516) — © The Trustees of the Natural History Museum, London, Natural History Museum (London) Data Portal, CC BY 4.0
Diplomystus dentatus — Diplomystus dentatus Cope, 1877 (NHMUK PV P 7489)
Diplomystus dentatus Cope, 1877 (NHMUK PV P 7489) — © The Trustees of the Natural History Museum, London, Natural History Museum (London) Data Portal, CC BY 4.0
Diplomystus dentatus — Diplomystus birdi Woodward, 1895, HOLOTYPE (NHMUK PV P 96)
Diplomystus birdi Woodward, 1895, HOLOTYPE (NHMUK PV P 96) — © 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. "Diplomystus dentatus" (Taxon). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/taxa/diplomystus-dentatus. Accessed 2026-09-20.

BibTeX · CSL-JSON

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

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