Hypsilophodontidae

Hypsilophodontidae is a traditionally used family of ornithopod dinosaurs, generally considered invalid today. It historically included many small bodied bipedal neornithischian taxa from around the world, and spanning from the Middle Jurassic until the Late Cretaceous. This inclusive status was supported by some phylogenetic analyses from the 1990s and mid 2000s, although there have also been many finding that the family is an unnatural grouping which should only include the type genus, Hypsilophodon, with the other genera being within clades like Thescelosauridae and Elasmaria. A 2014 analysis by Norman recovered a grouping of Hypsilophodon, Rhabdodontidae and Tenontosaurus, which he referred to as Hypsilophodontia. That clade is formally defined in the PhyloCode as "the smallest clade within Ornithopoda containing Hypsilophodon foxii and Tenontosaurus tilletti provided it does not include Iguanodon bernissartensis". All other analyses from around the same time have instead found these latter taxa to be within Iguanodontia. The family Hypsilophodontidae is formally defined in the PhyloCode by Daniel Madzia and colleagues in 2021 as "the largest clade containing Hypsilophodon foxii, but not Iguanodon bernissartensis and Rhabdodon priscus".

Hypsilophodontidae

No machine-readable author provided. Casliber assumed (based on copyright claims). · Public Domain · via Wikipedia/Commons. May be a photograph of a specimen, or an artist’s reconstruction — an interpretation of a skeleton, since colour and soft tissue are almost never preserved.

On record

Recorded, not inferred
Also called
hypsilophodontidPBDB
Sits inside
OrnithopodaPBDB
Diet
herbivorePBDB, for Ornithopoda
Life habit
ground dwelling, gregariousPBDB, for Ornithischia
Motility
actively mobilePBDB, for Ornithischia
Environment
terrestrialPBDB, for Ornithischia

Time the record covers

At least 93 million years on record.

The record covers at least 165.3 Mya to 72.2 Mya. No occurrence read is dated outside 168.2 Mya to 66 Mya.

Middle Jurassic — about 3 of 79 occurrencesMiddle JurassicLate Jurassic — about 5 of 79 occurrencesLate JurassicEarly Cretaceous — about 40 of 79 occurrencesEarly CretaceousLate Cretaceous — about 31 of 79 occurrencesLate CretaceousPaleocene — about 0 of 79 occurrences170–167 Mya — about 2 occurrences167–163 Mya — about 1 occurrence156–153 Mya — about 0.8 occurrences153–149 Mya — about 1 occurrence149–145 Mya — about 2 occurrences145–142 Mya — about 2 occurrences142–138 Mya — about 2 occurrences138–135 Mya — about 2 occurrences135–131 Mya — about 1 occurrence131–128 Mya — about 2 occurrences128–124 Mya — about 8 occurrences124–121 Mya — about 13 occurrences121–117 Mya — about 3 occurrences117–114 Mya — about 2 occurrences114–110 Mya — about 2 occurrences110–106 Mya — about 0.7 occurrences106–103 Mya — about 1 occurrence103–99 Mya — about 3 occurrences99–96 Mya — about 6 occurrences96–92 Mya — about 3 occurrences89–85 Mya — about 0.2 occurrences85–82 Mya — about 3 occurrences82–78 Mya — about 4 occurrences78–75 Mya — about 4 occurrences75–71 Mya — about 4 occurrences71–67 Mya — about 4 occurrences67–64 Mya — about 2 occurrences165.3 Mya72.2 Mya170 Mya64 Mya

79 occurrences of Hypsilophodontidae on record, most of them in the Early Cretaceous. Bar height is expected occurrences, not a count: each fossil is spread across the span it is dated to, so a tall narrow bar means tight dating and a low wide one means loose.

When

79 occurrences

These are dates about fossils, not the animal: the record can only begin after it arose and end before it died out, so either end may reach further. Shares are expected occurrences: a fossil dated to a span is counted partly in each period it straddles. More on what this infers.

Found in

44 formations

Griman Creek — 29.45°S, 147.78°EGriman Creek — 29.45°S, 147.76°EGriman Creek — 29.44°S, 147.73°EHell Creek — 47.62°N, 107.32°WHell Creek — 47.55°N, 107.10°WHell Creek — 47.52°N, 106.40°WHell Creek — 47.60°N, 106.27°WHell Creek — 47.87°N, 106.18°WTwo Medicine — 48.63°N, 113.75°WTwo Medicine — 48.48°N, 112.70°WTwo Medicine — 48.30°N, 112.34°WTwo Medicine — 47.77°N, 112.29°WWessex — 50.62°N, 1.37°WCedar Mountain — 38.83°N, 109.57°WCedar Mountain — 38.69°N, 111.26°WIlek — 55.90°N, 87.96°EIlek — 56.53°N, 91.81°EArtoles — 40.82°N, 0.28°WCamarillas — 40.65°N, 0.88°WCamarillas — 40.67°N, 0.67°WEl Castellar — 40.67°N, 0.67°WEl Castellar — 40.56°N, 0.68°WJudith River — 46.46°N, 109.41°WJudith River — 46.76°N, 108.00°WPinilla de los Moros — 42.02°N, 3.23°WPinilla de los Moros — 42.15°N, 3.17°WArcillas de Morella — 40.49°N, 0.42°EArcillas de Morella — 40.59°N, 0.14°WWapiti — 55.25°N, 118.51°WCastrillo de la Reina — 41.93°N, 3.24°WVectis — 50.65°N, 1.47°WAntlers — 33.28°N, 97.62°WGrès à Reptiles — 43.53°N, 5.57°EWadi Milk — 16.70°N, 31.14°EMugher Mudstone — 9.45°N, 38.62°EKuwajima — 36.17°N, 136.63°EOkurodani — 36.05°N, 136.88°EBlesa — 40.95°N, 0.77°WCloverly — 45.26°N, 108.41°WChipping Norton Limestone — 51.99°N, 1.80°W

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The named rock units Hypsilophodontidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 20 further formations hold fewer occurrences each and are not listed. 8 occurrences have no formation on record, which is common for older literature.

Hypsilophodontidae and its relatives

Early Cretaceous

Where Hypsilophodontidae and its relatives were recorded in the Early Cretaceous.

Found in the same rock

692 taxa

The Paleobiology Database records 74 sites for Hypsilophodontidae, and this reads all of them. The number is how many of those sites it was catalogued from too. The 24 sharing the most are listed.

This is not a list of everything alive at the time. It is only what has come out of the same ground as this animal and been written down.

Entered from

61 references

Each of the 79 occurrences read was entered from one of these publications, ordered by how many each accounts for. This is not a search for papers mentioning the name. 49 further references are not listed. Entries link to doi.org where the Paleobiology Database holds an identifier, and to its own record where it does not. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.

Media and terms

Media content1

Picture of Hypsilophodontidae

Credit
No machine-readable author provided. Casliber assumed (based on copyright claims).
Licence
Public Domain
Commercial use
the licence allows it

No 3D scan of Hypsilophodontidae was found in MorphoSource and Sketchfab.

Smithsonian Open Access was not reached for this taxon, so this list is what the others held rather than everything there is.

The description on this site

Licence
CC BY-SA 4.0

This is what the site found, which is not the same as what exists.

Keep going

What may have been alongside itOrnithopoda through timeFormations of the Early CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Dollo 1882)