Eurypterida

Eurypterids, often informally called sea scorpions, are a group of extinct marine arthropods that form the order Eurypterida. The earliest known eurypterids date to the Tremadocian stage of the Ordovician period, 480 million years ago. The group is likely to have appeared first during the Late Cambrian period. With approximately 250 species, the Eurypterida is the most diverse Paleozoic chelicerate order. Following their appearance during the Ordovician, eurypterids became major components of marine faunas during the Silurian, from which the majority of eurypterid species have been described. The Silurian genus Eurypterus accounts for more than 90% of all known eurypterid specimens. Though the group continued to diversify during the subsequent Devonian period, the eurypterids were heavily affected by the Late Devonian extinction event. They declined in numbers and diversity during the Permian period, though their time of extinction remains contentious, argued to be either the early Middle Permian, or the Permian–Triassic extinction event 251.9 million years ago.

Eurypterida

H. Zell · CC BY-SA 3.0 · 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
Also called
eurypteridPBDB
Sits inside
ChelicerataPBDB
Diet
carnivorePBDB
Life habit
nektobenthicPBDB
Motility
actively mobilePBDB
Vision
well-developedPBDB

Time the record covers

At least 204 million years on record.

The record covers at least 458.2 Mya to 254.14 Mya. No occurrence read is dated outside 469.4 Mya to 251.902 Mya.

Ordovician — about 17 of 603 occurrencesOrdovicianSilurian — about 360 of 603 occurrencesSilurianDevonian — about 149 of 603 occurrencesDevonianCarboniferous — about 68 of 603 occurrencesCarboniferousPermian — about 9 of 603 occurrencesPermianEarly Triassic — about 0 of 603 occurrences474–466 Mya — about 0.3 occurrences466–459 Mya — about 0.7 occurrences459–451 Mya — about 4 occurrences451–444 Mya — about 11 occurrences444–436 Mya — about 39 occurrences436–429 Mya — about 73 occurrences429–421 Mya — about 186 occurrences421–413 Mya — about 130 occurrences413–406 Mya — about 33 occurrences406–398 Mya — about 20 occurrences398–391 Mya — about 7 occurrences391–383 Mya — about 6 occurrences383–376 Mya — about 4 occurrences376–368 Mya — about 4 occurrences368–361 Mya — about 6 occurrences361–353 Mya — about 5 occurrences353–346 Mya — about 4 occurrences346–338 Mya — about 4 occurrences338–330 Mya — about 2 occurrences330–323 Mya — about 4 occurrences323–315 Mya — about 17 occurrences315–308 Mya — about 14 occurrences308–300 Mya — about 19 occurrences300–293 Mya — about 4 occurrences293–285 Mya — about 3 occurrences285–278 Mya — about 2 occurrences278–270 Mya — about 0.8 occurrences255–248 Mya — about 1 occurrence458.2 Mya254.14 Mya474 Mya248 Mya

603 occurrences of Eurypterida on record, most of them in the Silurian. 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

603 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

203 formations

Shawangunk — 40.98°N, 75.14°WShawangunk — 41.47°N, 74.54°WReservoir — 56.00°N, 3.00°WReservoir — 55.81°N, 3.35°WBertie — 42.93°N, 75.12°WBertie — 43.45°N, 74.95°WBertie — 43.00°N, 78.07°WBertie — 42.88°N, 78.88°WBertie — 43.05°N, 76.15°WPozary — 49.93°N, 14.18°EPozary — 50.08°N, 14.47°EPozary — 49.90°N, 14.02°EPozary — 49.52°N, 13.50°ESundvollen — 60.17°N, 10.30°ESundvollen — 59.92°N, 10.75°EFiddlers Green — 42.85°N, 78.80°WSyracuse — 43.05°N, 76.15°WSyracuse — 43.07°N, 76.08°WSyracuse — 43.05°N, 76.00°WSyracuse — 43.07°N, 76.33°WSyracuse — 43.05°N, 76.15°WDownton Castle Sandstone — 51.37°N, 2.73°WDownton Castle Sandstone — 52.37°N, 2.73°WDownton Castle Sandstone — 52.43°N, 2.81°WTemeside Shale — 52.37°N, 2.73°WSteinsfjorden — 60.17°N, 10.30°ESteinsfjorden — 59.90°N, 10.53°ESteinsfjorden — 60.03°N, 10.28°EVernon Shale — 43.08°N, 77.52°WWills Creek — 38.95°N, 79.00°WWills Creek — 39.65°N, 78.76°WDundee Flagstone — 57.00°N, 4.00°WDundee Flagstone — 56.67°N, 2.77°WRootsikula — 58.42°N, 22.50°ELochkov — 50.08°N, 14.47°ELochkov — 49.50°N, 14.33°ELochkov — 49.93°N, 14.18°EKip Burn — 55.65°N, 3.92°WWabash — 40.48°N, 86.18°WWabash — 40.49°N, 86.13°WPatrick Burn — 55.65°N, 3.92°WPatrick Burn — 55.61°N, 3.99°WBear Rock — 68.18°N, 125.84°WKlerf — 50.25°N, 6.46°EKokomo — 40.48°N, 86.13°WSlot Burn — 55.65°N, 3.92°WWhitcliffe — 52.37°N, 2.72°WWhitcliffe — 52.07°N, 2.65°WHogklint — 57.57°N, 18.30°E

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The named rock units Eurypterida has been recovered from, largest first. Drawn where the rock is now, not where it formed. 179 further formations hold fewer occurrences each and are not listed. 69 occurrences have no formation on record, which is common for older literature.

Eurypterida and its relatives

Silurian

Where Eurypterida and its relatives were recorded in the Silurian.

Found in the same rock

1,633 taxa

The Paleobiology Database records 311 sites for Eurypterida, and this reads 240 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

183 references

Each of the 603 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. 171 further references are not listed. 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 Eurypterida

Credit
H. Zell
Licence
CC BY-SA 3.0
Commercial use
the licence allows it

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
Commercial use
the licence does not allow it

Smithsonian Open Access and MorphoSource were 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 itChelicerata through timeFormations of the SilurianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Huxley 1857)