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 11 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.
- Species named in its records
- Segnosaurus galbinensis
Sources
Given by: Paleobiology Database (the species its fossil records are identified as).
- Diet
- herbivore (inferred for its group)
medium
medium: Only PBDB gives this, and it infers it for the whole of Therizinosauroidea, 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)
low
low: PBDB infers this way of life for the whole of Therizinosauroidea; 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).
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 the name in quotation marks).
- Resting on one source: 5 facts come from a single source with nothing against them (rated medium): type species (PBDB); parent group (PBDB); family (PBDB); age (headline) (PBDB); 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. 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.
Connections
Genera linked to Segnosaurus by where and when their fossils were found, by classification and by who named them. Select a name to open its page.
Same rocks, same time 12
Genera found in the same rock units, from rocks of overlapping age, the most shared fossil sites first.
Same family: Therizinosauridae 5
Other genera in Therizinosauridae with a full profile.
Named by Perle 2
Genera whose naming authority includes the same surname. The authority has no initials, so different people who share a surname can appear together.
Found in Mongolia 21
Other genera found in Mongolia, from rocks of overlapping age, the most fossil sites there first.
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.