Dinosaur genus
Hypsilophodon
Hypsilophodon is a dinosaur genus known from bones, found in rocks 143.1–100.5 million years old, in 4 countries, most often the United Kingdom 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 5 October 2026- Named by
- Huxley 1870
medium
medium: PBDB and Wikidata agree on who named it; Wikidata gives the year as 1869, one year apart, as when a work is dated one year and comes out the next.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Described in
- T. H. Huxley (1870). On Hypsilophodon foxii, a new dinosaurian from the Wealden of the Isle of Wight. Quarterly Review of the Geological Society of London 26: 3–12. Read it
medium
medium: Only PBDB gives this; its author and year match the naming authority (Huxley 1870).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 Aptian, 154.8–119.6 million years ago
disputed
low: Sources disagree and an editor has not ruled yet.Omnisaura calculation143.1–100.5 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
- United KingdomJapan
high
high: NHM and PBDB both record it.Portugallow
low: Only one PBDB record.Romanialow
low: Only one PBDB record.low
low: Only one PBDB record.mixed
mixed: Levels differ between entries; each has its own.Sources
Given by: Paleobiology Database; Natural History Museum Data Portal. How it was chosen: Union of all sources (ISO 3166).
- Rock formations
- Wessex FormationLourinhã
high
high: NHM and PBDB both record it.Lower Bauxitelow
low: Only one PBDB record.Vectis Formationlow
low: Only one PBDB record.low
low: Only one PBDB record.mixed
mixed: Levels differ between entries; each has its own.Sources
Given by: Paleobiology Database; Natural History Museum Data Portal. How it was chosen: Canonical names, automatic and editor-approved matches applied.
- Family
- Hypsilophodontidae
high
high: PBDB and NHM agree.Sources
Given by: Paleobiology Database; Natural History Museum Data Portal. How it was chosen: PBDB leads.
- Parent group
- Hypsilophodontidae
medium
medium: Only PBDB gives this; nothing contradicts it.Sources
Given by: Paleobiology Database. How it was chosen: PBDB leads.
- Order
- Ornithischia
medium
medium: Only NHM gives this; nothing contradicts it.Sources
Given by: Natural History Museum Data Portal. How it was chosen: Gap filled from NHM.
- Species named in its records
- Hypsilophodon foxii
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; nothing contradicts it.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)
medium
medium: Only PBDB gives this; nothing contradicts it.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
- Type species: 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: 3 fossil records left out: identified only tentatively (for example "cf.", "?" or the name in quotation marks).
- Resting on one source: 4 facts come from a single source with nothing against them (rated medium): parent group (PBDB); order (NHM); diet (PBDB); way of life (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
1 openAge
- 154.8–119.57 MaPBDB
- 149.2–100.5 MaPBDB's own confirmed records
The ages of the records reach well beyond the published range. An editor hasn't ruled yet, so this is rated low until they do.
Did it meet…?
No. Hypsilophodon had gone at least 16.9 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 Hypsilophodon 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 11
Genera found in the same rock units, from rocks of overlapping age, the most shared fossil sites first.
Named by Huxley 1
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 United Kingdom 14
Other genera found in United Kingdom, 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
- Natural History Museum Data PortalCC0 1.0 · catalogued specimens
- 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.