Aristonectes fossil map
Where fossils of Aristonectes have been found, shown on the Earth as it looked about 66 million years ago and on today’s map.
Dots are fossil collections recorded in the Paleobiology Database. The “then” view moves today’s fossil sites back to their positions 66 million years ago (the time slice nearest the median age of the fossils) using the Merdith et al. (2021) plate model; positions are approximate. Open on the timeline map →
| Group | Plesiosaurs & kin |
|---|---|
| Lived | 83.6–66 million years ago (Campanian to Maastrichtian) |
| Periods | Cretaceous |
| Family | Elasmosauridae |
| Named by | Cabrera 1941 |
| Fossil records | 12 occurrences at 11 locations (PBDB) |
| Found in | Chile, Antarctica, Argentina |
| Rock formations | Quiriquina, López de Bertodano, Lopez de Bertodano, Lefipán, Allen, Dorotea |
About Aristonectes
Aristonectes (meaning "best swimmer") 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.
Text in “About” is quoted from the Wikipedia article Aristonectes (revision 1370050024), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 23 October 2026. Ages are those of the rock layers the fossils were found in. Wikidata: Q2154474.
