Jurassic
Hesperosaurus
Hesperosaurus mjosi
The catalogue presents Hesperosaurus as a herbivore member of Stegosauridae that lived during the Jurassic, between 156.3–152.1 Ma. Its estimated range is 6.0–7.0 m in length and 2.0–3.0 t in mass, giving a practical sense of scale. Reference material comes from Morrison Formation, Wyoming, USA. Size and mass are approximations and may change with new fossils or methods.
Evidence-backed summary
For Hesperosaurus, the PBDB records the taxonomic attribution as Carpenter et al. (2001).
The PBDB places it in Stegosaurinae, and the catalogue record assigns it to the family Stegosauridae.
- PBDB · taxon.parent
- Stegosauridae
The PBDB catalogues 6 occurrences, with material from the Morrison Formation (6). Provenance: United States.
The catalogue records the type locality as “Morrison Formation, Wyoming, USA”.
- Morrison Formation, Wyoming, USA
The catalogue's reference measurements are 6.0–7.0 m in length and 2.0–3.0 t in mass — estimates, which vary with specimen and method.
- 6.0-7.0 m
- 2.0-3.0 tons
The record gathers 14 bibliographic references registered in the PBDB, listed below.
Where it lived
Fossil occurrences on today’s map and in the tectonic reconstruction.
Positions reconstructed by PBDB/GPlates, not observed; this is not an exact habitat map.
Artistic 3D reconstruction
There is no approved species-specific 3D model yet. Generic anatomy will not be presented as if it were evidence.
Physical Specifications
- Length
- 6.0–7.0 m
- Weight
- 2.0–3.0 t
- Period
- Jurassic
- Time range
- 156.3–152.1 Ma
Discovery Information
- First Discovery
- 2001
- Described by
- Carpenter et al.
Taxonomic Classification
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Reptilia
- Order
- Ornithischia
- Family
- Stegosauridae
- Genus
- Hesperosaurus
- Species
- H. mjosi
Data status
Taxonomic name matched to PBDB and checked on 2026-08-08.
Taxonomic linkage does not automatically validate size, mass, behaviour or appearance.
- Type specimen
- not documented in this catalogue
- Type locality
- Morrison Formation, Wyoming, USA