Omnisaura

Dinosaur genus

Chaoyangsaurus

Zhao et al. 1999

Chaoyangsaurus is a dinosaur genus known from bones, found in rocks 152.2–132.6 million years old, in China.

Confidence labels
How sure are we?2 high5 medium4 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 11 October 2026
152.2–132.6 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
Zhao et al. 1999
highhigh: PBDB and Wikidata agree.
Sources

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

Described in
X. Zhao, Z. Cheng, X. Xu (1999). The earliest ceratopsian from the Tuchengzi Formation of Liaoning, China. Journal of Vertebrate Paleontology 19(4): 681–697. Read it
highhigh: PBDB gives this publication for the name; its author and year match the naming authority (Zhao et al. 1999), on which PBDB and Wikidata agree.
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.

Lived
Kimmeridgian to Valanginian, 152.2–132.6 million years ago
mediummedium: Only PBDB gives this; nothing contradicts it.
Omnisaura calculation152.2–132.6 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
China
lowlow: Only one PBDB record.
Sources

Given by: Paleobiology Database. How it was chosen: Union of all sources (ISO 3166).

Rock formations
Tuchengzi
lowlow: Only one PBDB record.
Sources

Given by: Paleobiology Database. How it was chosen: Canonical names, automatic and editor-approved matches applied.

Family
Chaoyangsauridae
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

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

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

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

Named after
Chaoyang
mediummedium: Only Wikidata gives this; nothing contradicts it.
Sources

Given by: Wikidata. How it was chosen: Wikidata leads.

Older or other names
Chaoyangosaurus (a name it replaced)
Sources

Given by: Paleobiology Database (names it treats as this genus).

Diet
herbivore (inferred for its group)
mediummedium: Only PBDB gives this, and it infers it for the whole of Ceratopsia, the group this genus belongs to, not from this genus's own fossils.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB, inferred from a group the genus belongs to.

Way of life
ground dwelling (inferred for its group)
lowlow: PBDB infers this way of life for the whole of Ceratopsia; behaviour is rarely known for one genus.
Sources

Given by: Paleobiology Database. How it was chosen: PBDB, inferred from a group the genus belongs to.

Known from
Bones
Sources

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

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

Gaps are answers

What isn't known yet

  • Type species: no source we use gives it yet.
  • Order: no source we use gives it yet.
  • Common names: no source we use gives it yet.
  • Resting on one source: 5 facts come from a single source with nothing against them (rated medium): parent group (PBDB); family (PBDB); age (headline) (PBDB); named after (Wikidata); diet (PBDB).

Size and appearance aren't covered yet, and diet and way of life only as PBDB infers them for the wider group. Omnisaura leaves the rest out rather than guess.

Where sources disagree

None open. Where our sources overlap, they agree on everything shown here.

Did it meet…?

?

No. Chaoyangsaurus had gone at least 49 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.

Connections

Genera linked to Chaoyangsaurus by where and when their fossils were found, by classification and by who named them. Select a name to open its page.

ChaoyangsaurusSame rocks, same timeSame naming authorAlso found in ChinaGrallatorTherangospodusBrontopodusMegalosauripusand 1 moreChangdusaurusDendroolithusDictyoolithusElongatoolithusand 10 morePsittacosaurusMamenchisaurusEubrontesJialingpusand 23 more

Same rocks, same time 5

Genera found in the same rock units, from rocks of overlapping age, the most shared fossil sites first.

GrallatorTherangospodusBrontopodusMegalosauripusMenglongipus

Named by Zhao 14

Genera whose naming authority includes the same surname. The authority has no initials, so different people who share a surname can appear together.

ChangdusaurusDendroolithusDictyoolithusElongatoolithusFaveoloolithusMacroolithusNanhsiungoolithusOvaloolithusParaspheroolithusPlacoolithusPrismatoolithusShixingoolithusSinraptorSpheroolithus

Credits

Where this page comes from

  • Paleobiology DatabaseCC BY 4.0 · fossil records, ages, classification
  • 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.