Omnisaura

Dinosaur genus

Tawa

Nesbitt et al. 2009

Tawa is a dinosaur genus known from bones, found in rocks 227.3–205.7 million years old, in the United States.

Confidence labels
How sure are we?0 high7 medium0 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
227.3–205.7 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
Nesbitt et al. 2009
mediummedium: Only PBDB gives this; nothing contradicts it.
Sources

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

Described in
S. J. Nesbitt, N. D. Smith, R. B. Irmis, A. H. Turner, A. Downs, M. A. Norell (2009). A complete skeleton of a Late Triassic saurischian and the early evolution of dinosaurs. Science 326: 1530–1533. Read it
mediummedium: Only PBDB gives this; its author and year match the naming authority (Nesbitt et al. 2009).
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
Norian, 227.3–205.7 million years ago
mediummedium: Only PBDB gives this; nothing contradicts it.
Omnisaura calculation227.3–205.7 million years ago, from its dated fossil records
mediummedium: Omnisaura's calculation from 3 confirmed PBDB records.
Sources

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

Fossils found in
United States
mediummedium: Only PBDB records it (3 records).
Sources

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

Rock formations
Chinle
mediummedium: Only PBDB records it (3 records).
Sources

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

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

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

Species named in its records
Tawa hallae
Sources

Given by: Paleobiology Database (the species its fossil records are identified as).

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.
  • Family: no source we use gives it yet.
  • Diet: no source we use gives it yet.
  • Way of life: 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: 3 facts come from a single source with nothing against them (rated medium): authority (PBDB); parent group (PBDB); age (headline) (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. Tawa had gone at least 122.1 million years before Tyrannosaurus appears in the fossil record, a longer gap than the 66 million years between Tyrannosaurus and today.

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

TawaSame rocks, same timeSame parent groupSame naming authorAlso found in United StatesCoelophysisKrzyzanowskisaurusKwanasaurusBarrancapusand 6 moreAlwalkeriaAnticheiropusArgoidesChindesaurusand 7 moreAlbinykusAsilisaurusGrallatorEubrontesEvazoumAnomoepusand 18 more

Same rocks, same time 10

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

CoelophysisKrzyzanowskisaurusKwanasaurusBarrancapusCamposaurusChindesaurusEosauropusEubrontesEucoelophysisGrallator

Named by Nesbitt 2

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

AlbinykusAsilisaurus

Found in United States 22

Other genera found in United States, from rocks of overlapping age, the most fossil sites there first.

GrallatorEubrontesCoelophysisEvazoumAnomoepusEosauropusAnchisauripusAtreipusBarrancapusCoelurosaurichnusGregaripusKayentapusKrzyzanowskisaurusKwanasaurusPseudotetrasauropusArgoidesand 6 more

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.