Dinosaur genus
Segnosaurus
Segnosaurus is a dinosaur genus known from bones, found in rocks 100.5–83.6 million years old, in Mongolia and Japan.
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
- Perle 1979
high
high: PBDB and Wikidata agree.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Described in
- A. Perle (1979). Segnosauridae - novoe semeistvo teropod is posdnego mela Mongolii [Segnosauridae - a new family of theropods from the Late Cretaceous of Mongolia]. Trudy - Sovmestnaya Sovetsko-Mongol'skaya Paleontologicheskaya Ekspeditsiya 8: 45–55.
high
high: PBDB gives this publication for the name; its author and year match the naming authority (Perle 1979), 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.
- Type species
- Segnosaurus galbinensis
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Lived
- Cenomanian to Santonian, 100.5–83.6 million years ago
medium
medium: Only PBDB gives this; nothing contradicts it.Omnisaura calculation100.5–83.6 million years ago, from its dated fossil recordsmedium
medium: Omnisaura's calculation from 5 confirmed PBDB records.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Fossils found in
- JapanMongolia
medium
medium: Only PBDB records it (2 records).medium
medium: Only PBDB records it (3 records).Sources
Given by: Paleobiology Database. How it was chosen: Union of all sources (ISO 3166).
- Rock formations
- BaynshireJobu
medium
medium: Only PBDB records it (3 records).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
- Therizinosauridae
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Parent group
- Therizinosauridae
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Known from
- Bones
Sources
Given by: Paleobiology Database (what the name was based on).
Gaps are answers
What isn't known yet
- Order: 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.
- Held back: 1 fossil record left out: identified only tentatively (for example "cf." or "?").
- Resting on one source: 4 facts come from a single source with nothing against them (rated medium): type species (PBDB); parent group (PBDB); family (PBDB); age (headline) (PBDB).
Size, diet and behaviour aren't covered yet. Omnisaura leaves them out rather than guess.
Where sources disagree
None open. Where our sources overlap, they agree on everything shown here.
Did it meet…?
No. Segnosaurus had gone at least 0 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 Therizinosauridae 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.