Megachelicerax fossil map
Where fossils of Megachelicerax have been found, shown on the Earth as it looked about 500 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 500 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 | Ediacaran & Cambrian life |
|---|---|
| Lived | 504.5–500.5 million years ago (Drumian) |
| Periods | Cambrian |
| Named by | Lerosey-Aubril and Ortega-Hernández 2026 |
| Fossil records | 1 occurrences at 1 locations (PBDB) |
| Found in | United States |
| Rock formations | Wheeler Shale |
About Megachelicerax
Megachelicerax is an extinct genus of stem-chelicerate that lived in Utah during the middle Cambrian. It contains only a single species; Megachelicerax cousteaui. As the oldest known arthropod to bear chelicerae, Megachelicerax is significant in the evolutionary history of chelicerates, as it represents an important transitional stage between stem-group chelicerates like Habeliida and members of Euchelicerata.
Text in “About” is quoted from the Wikipedia article Megachelicerax (revision 1351370890), 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: Q138972129.
