Aristonectes

Aristonectes is an extinct genus of large elasmosaurid plesiosaurs that lived during the Maastrichtian stage of the Late Cretaceous. Two species are known, A. parvidens and A. quiriquinensis, whose fossil remains were discovered in what are now Patagonia and Antarctica. Throughout the 20th century, Aristonectes was a difficult animal for scientists to analyze due to poor fossil preparation, its relationships to other genera were uncertain. After subsequent revisions and discoveries carried out from the beginning of the 21st century, Aristonectes is now recognised as the type genus of the subfamily Aristonectinae, a lineage of elasmosaurids characterized by an enlarged skull and a reduced length of the neck.

Aristonectes

Connor Ashbridge · CC BY-SA 4.0 · 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
AristonectinaePBDB
Diet
carnivorePBDB, for Plesiosauria
Life habit
aquatic, depth=surfacePBDB, for Plesiosauria
Motility
actively mobilePBDB, for Plesiosauria
Environment
marinePBDB, for Plesiosauria

Time the record covers

At most 18 million years on record.

Every occurrence read is dated to somewhere between 83.6 Mya and 66 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Late Cretaceous — about 12 of 12 occurrencesLate CretaceousPaleocene — about 0 of 12 occurrences84–83 Mya — about 0.0 occurrences83–83 Mya — about 0.0 occurrences83–82 Mya — about 0.0 occurrences82–82 Mya — about 0.0 occurrences82–81 Mya — about 0.0 occurrences81–80 Mya — about 0.0 occurrences80–80 Mya — about 0.0 occurrences80–79 Mya — about 0.0 occurrences79–79 Mya — about 0.0 occurrences79–78 Mya — about 0.0 occurrences78–77 Mya — about 0.0 occurrences77–77 Mya — about 0.0 occurrences77–76 Mya — about 0.0 occurrences76–75 Mya — about 0.0 occurrences75–75 Mya — about 0.0 occurrences75–74 Mya — about 0.0 occurrences74–74 Mya — about 0.0 occurrences74–73 Mya — about 0.0 occurrences73–72 Mya — about 0.0 occurrences72–72 Mya — about 0.9 occurrences72–71 Mya — about 1 occurrence71–70 Mya — about 1 occurrence70–70 Mya — about 1 occurrence70–69 Mya — about 1 occurrence69–69 Mya — about 1 occurrence69–68 Mya — about 1 occurrence68–67 Mya — about 1 occurrence67–67 Mya — about 1 occurrence67–66 Mya — about 1 occurrence66–66 Mya — about 0.2 occurrences84.1 Mya65.5 Mya

12 occurrences of Aristonectes on record, most of them in the Late 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

12 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

6 formations

Quiriquina — 36.61°S, 73.06°WQuiriquina — 36.59°S, 72.98°WLópez de Bertodano — 64.27°S, 56.72°WLópez de Bertodano — 63.86°S, 57.57°WLopez de Bertodano — 64.22°S, 56.72°WLopez de Bertodano — 64.25°S, 56.75°WLefipán — 42.67°S, 70.00°WAllen — 39.57°S, 66.98°WDorotea — 51.07°S, 72.50°W

Loading coastlines…

The named rock units Aristonectes 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.

Aristonectes and its relatives

Late Cretaceous

Where Aristonectes and its relatives were recorded in the Late Cretaceous.

Found in the same rock

67 taxa

The Paleobiology Database records 11 sites for Aristonectes, 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

9 references

Each of the 12 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 Aristonectes

Credit
Connor Ashbridge
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

3D model

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

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 itAristonectinae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Cabrera 1941