Dinosaur genus
Amargasaurus
Amargasaurus is a dinosaur genus known from bones, found in rocks 125.8–121.4 million years old, in Argentina.
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- Named by
- Bonaparte 1984
disputed
low: Sources disagree and an editor has not ruled yet.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Described in
- J. F. Bonaparte (1984). I dinosauri dell’Argentina [. Sulle Orme dei Dinosauri: 125–143.
medium
medium: Only PBDB gives this; its author and year match the naming authority (Bonaparte 1984).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
- Barremian, 125.8–121.4 million years ago
medium
medium: Only PBDB gives this; nothing contradicts it.Omnisaura calculation125.8–121.4 million years ago, from its dated fossil recordslow
low: Omnisaura's calculation from only 2 dated record(s).Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Fossils found in
- Argentina
medium
medium: Only PBDB records it (2 records).Sources
Given by: Paleobiology Database. How it was chosen: Union of all sources (ISO 3166).
- Rock formations
- La Amarga
medium
medium: Only PBDB records it (2 records).Sources
Given by: Paleobiology Database. How it was chosen: Canonical names, automatic and editor-approved matches applied.
- Family
- Dicraeosauridae
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Parent group
- Dicraeosaurinae
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Named after
- La Amarga Formation
medium
medium: Only Wikidata gives this; nothing contradicts it.Sources
Given by: Wikidata. How it was chosen: Wikidata leads.
- Known from
- Bones
Sources
Given by: Paleobiology Database (what the name was based on).
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: 4 facts come from a single source with nothing against them (rated medium): parent group (PBDB); family (PBDB); age (headline) (PBDB); named after (Wikidata).
Size, diet and behaviour aren't covered yet. Omnisaura leaves them out rather than guess.
Where sources disagree
1 openAuthority
- Bonaparte 1984PBDB (shown above)
- Leonardo Salgado, 1991Wikidata
The sources give different values. An editor hasn't ruled yet, so this is rated low until they do.
Did it meet…?
No. Amargasaurus had gone at least 37.8 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.
Same family
Other genera in Dicraeosauridae with a full profile.
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.