Allosaurus jimmadseni

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.

Allosaurus jimmadseni

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
AllosaurusPBDB
Diet
carnivorePBDB, for Theropoda
Life habit
ground dwelling, solitaryPBDB, for Theropoda
Motility
actively mobilePBDB, for Theropoda
Environment
terrestrialPBDB, for Theropoda

Time the record covers

At most 15 million years on record.

Every occurrence read is dated to somewhere between 157.9 Mya and 143.1 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Late Jurassic — about 7 of 7 occurrencesLate JurassicEarly Cretaceous — about 0 of 7 occurrences158–158 Mya — about 0.0 occurrences158–157 Mya — about 0.1 occurrences157–157 Mya — about 0.1 occurrences157–156 Mya — about 0.1 occurrences156–156 Mya — about 0.1 occurrences156–155 Mya — about 0.1 occurrences155–155 Mya — about 0.2 occurrences155–154 Mya — about 0.5 occurrences154–154 Mya — about 0.5 occurrences154–153 Mya — about 0.5 occurrences153–153 Mya — about 0.5 occurrences153–152 Mya — about 0.5 occurrences152–152 Mya — about 0.5 occurrences152–151 Mya — about 0.5 occurrences151–151 Mya — about 0.5 occurrences151–150 Mya — about 0.5 occurrences150–149 Mya — about 0.5 occurrences149–149 Mya — about 0.3 occurrences149–148 Mya — about 0.1 occurrences148–148 Mya — about 0.1 occurrences148–147 Mya — about 0.1 occurrences147–147 Mya — about 0.1 occurrences147–146 Mya — about 0.1 occurrences146–146 Mya — about 0.1 occurrences146–145 Mya — about 0.1 occurrences145–145 Mya — about 0.1 occurrences145–144 Mya — about 0.0 occurrences144–144 Mya — about 0.0 occurrences144–143 Mya — about 0.0 occurrences143–143 Mya — about 0.0 occurrences158.4 Mya142.6 Mya

7 occurrences of Allosaurus jimmadseni 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

7 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

1 formation

Morrison — 44.65°N, 107.82°WMorrison — 44.54°N, 107.78°WMorrison — 38.58°N, 108.40°WMorrison — 44.05°N, 107.46°WMorrison — 40.44°N, 109.29°WMorrison — 44.46°N, 104.73°W

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The named rock units Allosaurus jimmadseni has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Allosaurus jimmadseni and its relatives

Late Jurassic

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

Found in the same rock

92 taxa

The Paleobiology Database records 7 sites for Allosaurus jimmadseni, 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

3 references

Each of the 7 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. 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 content2

Picture of Allosaurus jimmadseni

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

3D model

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

Smithsonian Open Access and MorphoSource were 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 itAllosaurus through timeFormations of the Late JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Chure et al. 2006