Stratum.black
Champsosaurus — Champsosaurus
Champsosaurus — D. Gordon E. Robertson, Wikimedia Commons, CC BY SA 3.0

Reptile

Champsosaurus

Choristodere

Champsosaurus is a gharial-like choristodere reptile, not a crocodile, that lived in Late Cretaceous and Paleocene rivers of the northern Great Plains. Its small conical teeth with fluted, infolded enamel and its distinctive amphicoelous vertebrae are common in Hell Creek and Judith River microsites and are often mislabelled as crocodile. Complete skeletons are rare and mostly in museums.

PhylumChordata
ClassReptilia
OrderChoristodera
FamilyChampsosauridae
GroupReptile
Rank (PBDB)genus· Paleobiology Database
AuthorCope 1876· Paleobiology Database
Classification (PBDB)Chordata › Reptilia › Choristodera › NO_FAMILY_SPECIFIED· Paleobiology Database
Range (PBDB)100–56 Ma· Paleobiology Database
PBDB occurrences232· Paleobiology Database

Photographs

Champsosaurus — Champsosaurus Cope, 1876, NON-TYPE (NHMUK PV R 4291)
Champsosaurus Cope, 1876, NON-TYPE (NHMUK PV R 4291) — © 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. "Champsosaurus" (Taxon). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/taxa/champsosaurus. Accessed 2026-09-20.

BibTeX · CSL-JSON

@misc{stratum-champsosaurus,
  title        = {Champsosaurus},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/taxa/champsosaurus}},
  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.}
}

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