Omnisaura

Dinosaur genus

Calamosaurus

Lydekker 1891

Calamosaurus is a dinosaur genus known from bones, found in rocks 125.8–119.6 million years old, in the United Kingdom.

Confidence labels
How sure are we?2 high5 medium2 lowHow we rate confidence

Confidence labels are switched off. Facts with low confidence, or where sources disagree, still carry a small dot: tap it for the reason.

At a glance

Data as of 12 October 2026
125.8–119.6 Ma
Triassic
Jurassic
Cretaceous
252 million years ago20114366

The last non-bird dinosaurs died out 66 million years ago. That's as far from us as the end of this bar.

Named by
Lydekker 1891
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Described in
R. Lydekker (1891). On certain ornithosaurian and dinosaurian remains. Quarterly Journal of the Geological Society of London 47: 41–44. Read it
mediummedium: Only PBDB gives this; its author and year match the naming authority (Lydekker 1891).
Sources

Given by: Paleobiology Database. The publication the Paleobiology Database gives as the authority for this genus name, usually the one that first named and described it.

Type species
Calamosaurus foxi
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Lived
Barremian to Aptian, 125.8–119.6 million years ago
highhigh: PBDB and NHM agree.
Omnisaura calculation125.8–119.6 million years ago, from its dated fossil records
lowlow: Omnisaura's calculation from only 1 dated record(s).
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Fossils found in
United Kingdom
highhigh: NHM and PBDB both record it.
Sources

Given by: Paleobiology Database; Natural History Museum Data Portal. How it was chosen: Union of all sources (ISO 3166).

Rock formations
Wessex Formation
disputedlow: Only NHM gives this name and it matches no PBDB formation; awaiting an editor.
Sources

Given by: Natural History Museum Data Portal. How it was chosen: Canonical names, automatic and editor-approved matches applied.

Parent group
Tyrannosauroidea
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB leads.

Order
Saurischia
mediummedium: Only NHM gives this; nothing contradicts it.
Sources

Given by: Natural History Museum Data Portal. How it was chosen: Gap filled from NHM.

Known from
Bones
Sources

Given by: Paleobiology Database (what the name was based on).

Sources: Paleobiology Database (CC BY 4.0), Natural History Museum Data Portal (CC0 1.0), Wikidata (CC0 1.0)Confidence levels and gaps are Omnisaura's own assessment.

Gaps are answers

What isn't known yet

  • Family: no source we use gives it yet.
  • Common names: no source we use gives it yet.
  • What it was named after: no source we use gives it yet.
  • Resting on one source: 4 facts come from a single source with nothing against them (rated medium): authority (PBDB); type species (PBDB); parent group (PBDB); order (NHM).

Size, diet and behaviour aren't covered yet. Omnisaura leaves them out rather than guess.

Where sources disagree

1 open

Formations

  • NonePBDB
  • Wessex FormationNHM

One source names a formation the other does not. An editor hasn't ruled yet, so this is rated low until they do.

Did it meet…?

?

No. Calamosaurus had gone at least 36 million years before Tyrannosaurus appears in the fossil record.

Going by the ages and rock formations of their dated fossils, as on the map. Compare their fossil sites on the map.

Lived alongside

Genera found in the same rock formations, from rocks of the same age.

None in Omnisaura yet.

Same parent group

Other genera in Tyrannosauroidea with a full profile.

Credits

Where this page comes from

  • Paleobiology DatabaseCC BY 4.0 · fossil records, ages, classification
  • Natural History Museum Data PortalCC0 1.0 · catalogued specimens
  • WikidataCC0 1.0 · names and identifiers
  • OmnisauraOmnisaura editorial · confidence levels and gaps
  • PaleoMAP PaleoCoastlines (Kocsis and Scotese 2021)CC BY 4.0 · ancient coastlines on the small map
  • Natural EarthPublic domain · today's coastlines

Pictures linked from this page are credited beside each one, with their own licences; the full list is in the JSON download.