Alexandronectes fossil map
Where fossils of Alexandronectes have been found, shown on the Earth as it looked about 75 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 75 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 | Otero et al. 2016 |
| Fossil records | 1 occurrences at 1 locations (PBDB) |
| Found in | New Zealand |
| Rock formations | Conway |
About Alexandronectes
Alexandronectes is a genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the oceans of Late Cretaceous New Zealand. It contains one species, A. zealandiensis. Fossils of Alexandronectes were found in the Conway Formation of Canterbury, which can be dated to the Early Maastrichtian stage of the Cretaceous. Fossils of it were found around 1872 near the Waipara River, north of Christchurch, New Zealand.
Alexandronectes belongs to the elasmosaurid subfamily Aristonectinae based on the pterygoid structure and an A-shaped squamosal arch. However, it differs from other aristonectines in its smaller skull, different paroccipital processes, and different mandibular glenoid. A 2021 study used CT scans to create digital reconstructions of the holotype, and detected the stapes in the inner ear, marking the first time this bone has been found in an aristonectine. The study also found a recess in the floccular lobe of the cerebellum, which may have functioned to stabilise both the head and the retinal image of Alexandronectes. This is the first occurrence of this feature in an elasmosaurid.
Text in “About” is quoted from the Wikipedia article Alexandronectes (revision 1329426672), 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: Q52984900.
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