Eurypterus fossil map
Where fossils of Eurypterus have been found, shown on the Earth as it looked about 420 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 420 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 | Trilobites & sea scorpions |
|---|---|
| Lived | 443.1–307.4 million years ago (Rhuddanian to Moscovian) |
| Periods | Silurian, Devonian, Carboniferous |
| Family | Eurypteridae |
| Named by | De Kay 1825 |
| Fossil records | 47 occurrences at 34 locations (PBDB) |
| Found in | United States, Norway, Ukraine, Canada, UK, China, Sweden, Estonia, Russian Federation, Germany |
| Rock formations | Steinsfjorden, txn:237426, Bertie, Syracuse, Sintan Shale, Vernon Shale |
About Eurypterus
Eurypterus ( yoo-RIP-tər-əs) is an extinct genus of eurypterid, a group of organisms commonly called "sea scorpions". The genus lived during the Silurian period, from around 432 to 418 million years ago. Eurypterus is by far the most well-studied and well-known eurypterid. Eurypterus fossil specimens probably represent more than 95% of all known eurypterid specimens.
There are fifteen species belonging to the genus Eurypterus, the most common of which is E. remipes, the first eurypterid fossil discovered and the state fossil of New York.
Members of Eurypterus averaged at about 13 to 23 cm (5 to 9 in) in length, but the largest individual discovered was estimated to be 60 cm (24 in) long. They all possessed spine-bearing appendages and a large paddle they used for swimming. They were generalist species, equally likely to engage in predation or scavenging.
Text in “About” is quoted from the Wikipedia article Eurypterus (revision 1374831692), licensed under CC BY-SA 4.0; introduction excerpted verbatim, formatting removed. Ages, family, authority and fossil records: Paleobiology Database, accessed 22 October 2026. Ages are those of the rock layers the fossils were found in.
