Allosaurus

Allosaurus is a genus of theropod dinosaur that lived 155 to 143 million years ago during the late Jurassic period. The first fossil remains that could definitively be ascribed to this genus were described in 1877 by Othniel C. Marsh. The name "Allosaurus" means "different lizard", alluding to its lightweight vertebrae, which Marsh believed were unique. The genus has a very complicated taxonomy and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains come from North America's Morrison Formation, with material also known from the Alcobaça, Bombarral, and Lourinhã formations in Portugal. It was known for over half of the 20th century as Antrodemus, but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry returned the name "Allosaurus" to prominence. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles.

A picture published with the record for Allosaurus.

The_Wookies · CC BY 2.5 · 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
Sits inside
AllosauroideaPBDB
Diet
carnivorePBDB, for Theropoda
Life habit
ground dwelling, solitaryPBDB, for Theropoda
Motility
actively mobilePBDB, for Theropoda
Environment
terrestrialPBDB, for Theropoda
Length
8.5 mWikidata
Mass
6 tonneWikidata

Time the record covers

At least 9.1 million years on record.

The record covers at least 152.21 Mya to 143.1 Mya. No occurrence read is dated outside 161.5 Mya to 137.05 Mya.

Middle Jurassic — about 0 of 147 occurrencesLate Jurassic — about 146 of 147 occurrencesLate JurassicEarly Cretaceous — about 1 of 147 occurrencesEarly Cretaceous162–161 Mya — about 0.0 occurrences161–160 Mya — about 0.0 occurrences160–159 Mya — about 0.0 occurrences159–159 Mya — about 0.0 occurrences159–158 Mya — about 0.1 occurrences158–157 Mya — about 0.3 occurrences157–156 Mya — about 0.3 occurrences156–155 Mya — about 0.3 occurrences155–154 Mya — about 5 occurrences154–154 Mya — about 10 occurrences154–153 Mya — about 10 occurrences153–152 Mya — about 11 occurrences152–151 Mya — about 12 occurrences151–150 Mya — about 12 occurrences150–149 Mya — about 12 occurrences149–148 Mya — about 11 occurrences148–148 Mya — about 11 occurrences148–147 Mya — about 11 occurrences147–146 Mya — about 11 occurrences146–145 Mya — about 10 occurrences145–144 Mya — about 9 occurrences144–143 Mya — about 9 occurrences143–142 Mya — about 2 occurrences142–142 Mya — about 0.1 occurrences142–141 Mya — about 0.1 occurrences141–140 Mya — about 0.1 occurrences140–139 Mya — about 0.1 occurrences139–138 Mya — about 0.1 occurrences138–137 Mya — about 0.1 occurrences137–137 Mya — about 0.1 occurrences152.21 Mya143.1 Mya162 Mya136.6 Mya

147 occurrences of Allosaurus on record, most of them in the Late Jurassic. 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

147 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

4 formations

Morrison — 41.89°N, 106.04°WMorrison — 42.04°N, 106.39°WMorrison — 42.02°N, 106.05°WMorrison — 43.63°N, 108.20°WMorrison — 40.42°N, 109.21°WMorrison — 34.94°N, 107.13°WMorrison — 35.32°N, 106.94°WMorrison — 38.45°N, 107.40°WMorrison — 41.98°N, 106.14°WMorrison — 38.54°N, 105.22°WMorrison — 41.88°N, 106.08°WMorrison — 39.65°N, 105.19°WMorrison — 39.24°N, 109.00°WMorrison — 44.54°N, 107.78°WMorrison — 44.65°N, 107.82°WMorrison — 38.73°N, 111.27°WMorrison — 42.16°N, 105.91°WMorrison — 36.90°N, 102.83°WMorrison — 38.58°N, 108.40°WMorrison — 40.53°N, 109.39°WMorrison — 36.93°N, 102.97°WMorrison — 41.97°N, 106.29°WMorrison — 39.17°N, 109.25°WMorrison — 38.85°N, 108.48°WMorrison — 45.54°N, 110.62°WMorrison — 39.01°N, 110.37°WMorrison — 44.53°N, 103.83°WMorrison — 44.18°N, 103.34°WMorrison — 39.32°N, 110.69°WMorrison — 40.09°N, 105.94°WMorrison — 40.44°N, 109.30°WMorrison — 41.80°N, 106.59°WMorrison — 39.08°N, 108.65°WMorrison — 44.23°N, 103.38°WMorrison — 34.94°N, 107.60°WMorrison — 40.50°N, 109.17°WMorrison — 43.65°N, 106.78°WMorrison — 44.09°N, 106.78°WMorrison — 38.71°N, 109.74°WMorrison — 38.84°N, 111.15°WMorrison — 44.63°N, 107.81°WMorrison — 44.02°N, 104.24°WMorrison — 39.95°N, 106.56°WMorrison — 40.49°N, 105.21°WMorrison — 35.52°N, 106.82°WMorrison — 35.43°N, 107.83°WMorrison — 35.56°N, 106.92°WMorrison — 44.05°N, 107.46°WMorrison — 38.25°N, 110.81°WMorrison — 37.34°N, 108.75°WMorrison — 44.09°N, 106.87°WMorrison — 37.53°N, 103.68°WMorrison — 40.46°N, 108.39°WMorrison — 39.16°N, 108.73°WMorrison — 36.97°N, 103.39°WMorrison — 37.56°N, 109.20°WMorrison — 43.38°N, 108.12°WMorrison — 39.15°N, 108.77°WMorrison — 44.46°N, 104.73°WMorrison — 46.85°N, 108.79°WAlcobaça — 39.70°N, 8.80°WLourinhã — 39.85°N, 8.62°WLourinhã — 39.28°N, 9.33°WLepidotus Beds — 51.78°N, 10.07°E

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The named rock units Allosaurus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 1 occurrence has no formation on record, which is common for older literature.

Allosaurus and its relatives

Late Jurassic

Where Allosaurus and its relatives were recorded in the Late Jurassic.

Found in the same rock

376 taxa

The Paleobiology Database records 132 sites for Allosaurus, 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

74 references

Each of the 147 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. 62 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 content4

Picture of Allosaurus

Credit
The_Wookies
Licence
CC BY 2.5
Commercial use
the licence allows it

3D scan

Licence
CC0 — this site’s default, not the record’s
Commercial use
the licence allows it
Specimen
Allosaurus fragilis Marsh, 1877

Laser scan

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Allosaurus jimmadseni · DINO:DINO 11541

3D model

Source
Sketchfab
Licence
CC Attribution
Commercial use
cannot be read from the licence given — check the record

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 itAllosauroidea through timeFormations of the Late JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Marsh 1877