Jurassic
Ceratosaurus
Ceratosaurus nasicornis
The catalogue presents Ceratosaurus as a carnivore member of Ceratosauridae that lived during the Jurassic, between 156.3–145.0 Ma. Its estimated range is 5.5–7.0 m in length and 500–1000 kg in mass, giving a practical sense of scale. Reference material comes from Morrison Formation, Colorado, USA. Size and mass are approximations and may change with new fossils or methods.
Evidence-backed summary
For Ceratosaurus, the PBDB records the taxonomic attribution as Marsh (1884).
The PBDB places it in Ceratosauria, and the catalogue record assigns it to the family Ceratosauridae.
- PBDB · taxon.parent
- Ceratosauridae
The PBDB catalogues 6 occurrences, with material from the Morrison Formation (5) and from the Praia da Amoreira-Porto Novo Formation (1). Provenance: United States and Portugal.
The catalogue records the holotype as USNM 4735 and the type locality as “Morrison Formation, Colorado, USA”.
- USNM 4735
- Morrison Formation, Colorado, USA
The catalogue's reference measurements are 5.5–7.0 m in length and 500–1000 kg in mass — estimates, which vary with specimen and method.
- 5.5-7.0 m
- 500-1000 kg
The record gathers 121 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
- 5.5–7.0 m
- Weight
- 500–1000 kg
- Period
- Jurassic
- Time range
- 156.3–145.0 Ma
Discovery Information
- First Discovery
- 1884
- Described by
- Othniel Charles Marsh
Taxonomic Classification
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Reptilia
- Order
- Saurischia
- Family
- Ceratosauridae
- Genus
- Ceratosaurus
- Species
- C. nasicornis
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
- USNM 4735
- Type locality
- Morrison Formation, Colorado, USA