Plesiosaurus

Plesiosaurus is a genus of extinct, large marine sauropterygian reptile that lived during the Early Jurassic. It is known by nearly complete skeletons from the Lias of England. Measuring around 3.5 m (11 ft) long, it is distinguishable by its small head, long and slender neck, broad turtle-like body, a short tail, and two pairs of large, elongated paddles. It lends its name to the order Plesiosauria, of which it is an early, but fairly typical member. It contains only one species, the type, Plesiosaurus dolichodeirus. Other species once assigned to this genus, including P. brachypterygius, P. guilielmiimperatoris, and P. tournemirensis have been reassigned to new genera, such as Hydrorion, Seeleyosaurus and Microcleidus.

Plesiosaurus

the paleobear · CC BY 2.0 · 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
PlesiosauroideaPBDB
Diet
carnivorePBDB, for Plesiosauria
Life habit
aquatic, depth=surfacePBDB, for Plesiosauria
Motility
actively mobilePBDB, for Plesiosauria
Environment
marinePBDB, for Plesiosauria
Length
3.5 mWikidata

Time the record covers

At least 117 million years on record.

The record covers at least 201.4 Mya to 83.6 Mya. No occurrence read is dated outside 205.7 Mya to 66 Mya.

Late Triassic — about 6 of 55 occurrencesEarly Jurassic — about 21 of 55 occurrencesEarly JurassicMiddle Jurassic — about 1 of 55 occurrencesMiddle JurassicLate Jurassic — about 14 of 55 occurrencesLate JurassicEarly Cretaceous — about 6 of 55 occurrencesEarly CretaceousLate Cretaceous — about 6 of 55 occurrencesLate CretaceousPaleocene — about 0 of 55 occurrences208–204 Mya — about 3 occurrences204–199 Mya — about 10 occurrences199–194 Mya — about 7 occurrences194–189 Mya — about 4 occurrences189–184 Mya — about 3 occurrences184–179 Mya — about 1 occurrence179–175 Mya — about 0.5 occurrences175–170 Mya — about 0.4 occurrences170–165 Mya — about 0.1 occurrences165–160 Mya — about 1.0 occurrences160–155 Mya — about 0.3 occurrences155–150 Mya — about 6 occurrences150–146 Mya — about 6 occurrences146–141 Mya — about 1 occurrence141–136 Mya — about 0.5 occurrences136–131 Mya — about 1 occurrence131–126 Mya — about 1 occurrence126–121 Mya — about 0.1 occurrences116–112 Mya — about 0.2 occurrences112–107 Mya — about 0.8 occurrences107–102 Mya — about 2 occurrences102–97 Mya — about 0.6 occurrences97–92 Mya — about 0.5 occurrences92–87 Mya — about 1 occurrence87–83 Mya — about 2 occurrences83–78 Mya — about 0.7 occurrences78–73 Mya — about 0.7 occurrences73–68 Mya — about 0.7 occurrences68–63 Mya — about 0.3 occurrences201.4 Mya83.6 Mya208 Mya63 Mya

55 occurrences of Plesiosaurus on record, most of them in the Early 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

55 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

17 formations

Kimmeridge Clay — 51.74°N, 1.31°WKimmeridge Clay — 52.39°N, 0.20°EKimmeridge Clay — 51.75°N, 1.20°WKimmeridge Clay — 50.57°N, 2.45°WKimmeridge Clay — 51.56°N, 1.78°WCharmouth Mudstone — 50.73°N, 2.90°WCharmouth Mudstone — 50.72°N, 2.83°WWestbury — 51.60°N, 2.63°WWestbury — 51.82°N, 2.41°WGrès de Mortinsart — 49.70°N, 5.66°EArgiles de Châtillon — 50.72°N, 1.62°EBraunjura alpha & Braunjura beta — 48.90°N, 7.67°EPortland Stone — 51.55°N, 1.79°WLaidmore — 43.05°S, 172.76°ESundays River — 33.50°S, 21.62°EEagle Ford — 31.53°N, 97.21°WBlue Lias — 51.13°N, 2.73°WTamayama — 37.49°N, 141.04°EUpper Greensand — 51.40°N, 1.69°WWest Melbury Marly Chalk — 52.04°N, 0.15°WCalcaires à Spatangues — 47.80°N, 3.65°ECerritos Bayos — 22.56°S, 69.14°W"Franciscan-Knoxville shales" — 35.06°N, 120.26°W

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The named rock units Plesiosaurus has been recovered from, largest first. Drawn where the rock is now, not where it formed. 25 occurrences have no formation on record, which is common for older literature.

Plesiosaurus and its relatives

Early Jurassic

Where Plesiosaurus and its relatives were recorded in the Early Jurassic.

Found in the same rock

357 taxa

The Paleobiology Database records 47 sites for Plesiosaurus, 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

37 references

Each of the 55 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. 25 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 content3

Picture of Plesiosaurus

Credit
the paleobear
Licence
CC BY 2.0
Commercial use
the licence allows it

Structured light scan

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Plesiosaurus dolichodeirus · NHMUK:PAL:PV OR 22656

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 itPlesiosauroidea through timeFormations of the Early JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. de la Beche and Conybeare 1821