Ceratosaurus
Named by Marsh 1884 · Theropods
Lived 154.8–145 million years ago, in the Kimmeridgian to Tithonian stages of the Late Jurassic.Below: the genera most often found in the same fossil collections, on the same time scale.
Top: the whole age of dinosaurs, 251.9–66 million years ago; the outlined part is enlarged below. Each bar spans the ICS stages its well-dated fossil records fall in.
Ceratosaurus lived 154.8–145 million years ago, during the Kimmeridgian to Tithonian stages of the Late Jurassic. The Paleobiology Database lists 29 fossil records for it from 4 countries (United States, Portugal and Tanzania and others) — the 41st most of the 99 genera on this site.
Most of what is known comes from one rock unit: 66% of its records are from the Morrison Formation.
It is one of the more widespread genera here: records from 4 countries, 11th of 99.
Allosaurus appears in 52% of the collections that hold Ceratosaurus; Apatosaurus in 41%.
Its stage range spans about 9.8 million years (the 56th longest of 99); it is the 14th best-recorded of the 32 theropods here.
- Lived
- 154.8–145 Ma
- Stage
- Kimmeridgian–Tithonian
- Period
- Jurassic
- Group
- Theropods
- Fossil records
- 29 · #41 of 99
- Collections
- 29
- Countries
- 4
How it compares with the other 98
Each thin line is one genus on this site — darker where several share a value. The marked line is Ceratosaurus.
Fossil records
29
41st most of 99 genera
Countries with records
4
Shared with 14 other genera
Length of stage range
9.8 My
56th longest of 99 genera
Where its fossils were found
29 fossil records with coordinates, at present-day positions.
States and provinces
Countries
The rocks it comes from, and the company it kept
Share of its 29 fossil records by rock formation; then the genera most often dug up in the same collections.
- Morrison 19 · 66%
- Tendaguru 3 · 10%
- Lourinhã 3 · 10%
- Tacuarembó 2 · 7%
- Alcobaça 1 · 3%
- Praia da Amoreira-Porto Novo 1 · 3%
1 accepted species
The only species of Ceratosaurus accepted in PBDB
- Ceratosaurus nasicornisMarsh 1884 · 6 records
Records by stage
Well-dated records, by the stage of their mid-point age
Where it was buried
Depositional setting of its fossil sites, where known
- Crevasse splay4
- Pond3
- Channel2
- Coarse channel fill2
- Delta plain2
- Lagoonal1
Other theropods of its time
Same group, overlapping stage range, never found in the same collections. The amber band marks when Ceratosaurus lived.
- Megalosaurus168.2–113.2 MaUnited Kingdom, France
Also from the same formations
Data: Paleobiology Database, taxon 38600 (CC BY 4.0), retrieved 2026-10-27. Ages follow the ICS chart — see how ranges are worked out.