Stratum.black
Thescelosaurus — Thescelosaurus
Thescelosaurus — Nobu Tamura ( http://spinops.blogspot.com ), Wikimedia Commons, CC BY 2.5

Dinosaur

Thescelosaurus

Small ornithopod

Thescelosaurus is a 3–4 m bipedal ornithopod of the Hell Creek and Lance formations, one of the last non-avian dinosaurs. Its small leaf-shaped teeth with coarse marginal denticles and its robust limb bones are sold from Montana and Dakota ranches. It is the animal behind the 'dinosaur heart' story of 2000, which later proved to be a concretion.

PhylumChordata
ClassReptilia
OrderOrnithischia
FamilyThescelosauridae
GroupDinosaur
Rank (PBDB)genus· Paleobiology Database
AuthorGilmore 1913· Paleobiology Database
Classification (PBDB)Chordata › Ornithischia › NO_ORDER_SPECIFIED › Thescelosauridae· Paleobiology Database
Range (PBDB)93.9–66 Ma· Paleobiology Database
PBDB occurrences55· Paleobiology Database

Photographs

Thescelosaurus — Thescelosaurus sp
Thescelosaurus sp — Smithsonian Institution (NMNHPALEO), Smithsonian Open Access, CC0
Thescelosaurus — Thescelosaurus neglectus Gilmore, 1913
Thescelosaurus neglectus Gilmore, 1913 — Smithsonian Institution (NMNHPALEO), Smithsonian Open Access, CC0
Thescelosaurus — Thescelosaurus neglectus Gilmore, 1913
Thescelosaurus neglectus Gilmore, 1913 — Smithsonian Institution (NMNHPALEO), Smithsonian Open Access, CC0

Age

Formations

Elsewhere

Cite this article

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

BibTeX · CSL-JSON

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