Xiphosura

Xiphosura is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs. They first appear in the fossil record in the Early Ordovician, around 480 million years ago. Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera.

Xiphosura

Junnn11 · CC BY-SA 4.0 · 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
Sits inside
ProsomapodaPBDB
Diet
carnivorePBDB
Life habit
nektobenthicPBDB
Motility
actively mobilePBDB

Time the record covers

At least 502 million years on record.

The record covers at least 506.5 Mya to 3.6 Mya. No occurrence read is dated outside 538.8 Mya to 2.58 Mya.

Cambrian — about 2 of 254 occurrencesCambrianOrdovician — about 7 of 254 occurrencesSilurian — about 9 of 254 occurrencesDevonian — about 14 of 254 occurrencesDevonianCarboniferous — about 144 of 254 occurrencesCarboniferousPermian — about 14 of 254 occurrencesPermianEarly Triassic — about 11 of 254 occurrencesMiddle Triassic — about 21 of 254 occurrencesLate Triassic — about 4 of 254 occurrencesEarly Jurassic — about 3 of 254 occurrencesMiddle Jurassic — about 1 of 254 occurrencesLate Jurassic — about 14 of 254 occurrencesEarly Cretaceous — about 2 of 254 occurrencesLate Cretaceous — about 6 of 254 occurrencesPaleocene — about 0 of 254 occurrencesEocene — about 1 of 254 occurrencesOligocene — about 0 of 254 occurrencesMiocene — about 0 of 254 occurrencesPliocene — about 1 of 254 occurrencesPleistocene — about 0 of 254 occurrences550–531 Mya — about 0.2 occurrences531–513 Mya — about 0.6 occurrences513–495 Mya — about 0.4 occurrences495–476 Mya — about 3 occurrences476–458 Mya — about 2 occurrences458–440 Mya — about 3 occurrences440–421 Mya — about 7 occurrences421–403 Mya — about 7 occurrences403–385 Mya — about 1 occurrence385–366 Mya — about 3 occurrences366–348 Mya — about 8 occurrences348–330 Mya — about 1.0 occurrences330–311 Mya — about 82 occurrences311–293 Mya — about 58 occurrences293–275 Mya — about 13 occurrences275–256 Mya — about 0.2 occurrences256–238 Mya — about 31 occurrences238–220 Mya — about 2 occurrences220–201 Mya — about 3 occurrences201–183 Mya — about 3 occurrences183–165 Mya — about 1 occurrence165–147 Mya — about 10 occurrences147–128 Mya — about 4 occurrences128–110 Mya — about 2 occurrences110–92 Mya — about 4 occurrences92–73 Mya — about 0.9 occurrences73–55 Mya — about 1 occurrence55–37 Mya — about 0.3 occurrences37–18 Mya — about 0.7 occurrences18–0 Mya — about 1 occurrence506.5 Mya3.6 Mya550 Mya0 Mya

254 occurrences of Xiphosura on record, most of them in the Carboniferous. The Paleobiology Database records this as a living group, and the chart stops with its fossils rather than at the present. 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

254 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

106 formations

Carbondale — 41.34°N, 88.39°WCarbondale — 41.30°N, 88.15°WCarbondale — 41.22°N, 88.21°WSolnhofen — 48.91°N, 11.14°ESolnhofen — 49.00°N, 11.70°EGrès à Voltzia — 48.91°N, 7.20°EGrès à Voltzia — 48.82°N, 7.24°EGrès à Voltzia — 48.69°N, 7.38°EGrès à Voltzia — 48.78°N, 7.25°EGrès à Voltzia — 48.64°N, 7.45°EGrès à Voltzia — 48.53°N, 7.43°EGrès à Voltzia — 48.64°N, 7.44°EWellington — 38.64°N, 97.21°WWellington — 36.33°N, 97.28°WWellington — 38.13°N, 97.21°WWettin — 51.63°N, 11.95°EPennant Sandstone — 51.75°N, 3.40°WPennant Sandstone — 51.65°N, 3.24°WHeath — 46.95°N, 108.96°WMuschelkalk — 41.27°N, 1.12°EPennine Lower Coal Measures — 53.53°N, 2.51°WCoolbaun Coal — 52.80°N, 7.04°WAlmaznaya — 47.93°N, 38.20°EAlmaznaya — 48.28°N, 39.90°EDeadwood — 47.42°N, 105.59°WDeadwood — 47.15°N, 110.22°WSundvollen — 60.17°N, 10.30°ESundvollen — 59.92°N, 10.75°EBertie — 43.45°N, 74.95°WBertie — 42.88°N, 78.88°WWood Siding — 39.06°N, 96.05°WFarrington — 51.28°N, 2.46°WFarrington — 51.30°N, 2.43°WSolling — 51.46°N, 10.03°EStockton — 40.33°N, 74.65°WChadakoin — 42.13°N, 77.94°WChadakoin — 42.00°N, 80.00°WSmolyaninovskaya — 48.62°N, 38.00°ESmolyaninovskaya — 48.37°N, 39.05°EBelaya Kalitva — 48.31°N, 40.25°EPennant — 51.71°N, 3.91°WParrsboro — 45.43°N, 63.03°WPhilippovian — 57.44°N, 57.01°EPhilippovian — 57.41°N, 57.06°E

Loading coastlines…

The named rock units Xiphosura has been recovered from, largest first. Drawn where the rock is now, not where it formed. 82 further formations hold fewer occurrences each and are not listed. 88 occurrences have no formation on record, which is common for older literature.

Xiphosura and its relatives

Carboniferous

Where Xiphosura and its relatives were recorded in the Carboniferous.

Found in the same rock

1,617 taxa

The Paleobiology Database records 216 sites for Xiphosura, and this reads all 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

137 references

Each of the 254 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. 125 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 content1

Picture of Xiphosura

Credit
Junnn11
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan of Xiphosura was found in Sketchfab.

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 itProsomapoda through timeFormations of the CarboniferousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Latreille 1802)