Sipuncula

The Sipuncula or Sipunculida is a class containing about 162 species of marine annelid worms, that have secondarily lost their segmentation. Sipuncula was once considered a phylum of unsegmented worms, but was demoted to a class of Annelida, based on recent molecular work.

Sipuncula

EcologyWA · CC0 · 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
SchizocoelaPBDB

Time the record covers

At least 309 million years on record.

The record covers at least 458.2 Mya to 149.2 Mya. No occurrence read is dated outside 469.4 Mya to 145.06 Mya.

Ordovician — about 1 of 8 occurrencesOrdovicianSilurian — about 4 of 8 occurrencesDevonian — about 0 of 8 occurrencesCarboniferous — about 0 of 8 occurrencesPermian — about 0 of 8 occurrencesEarly Triassic — about 0 of 8 occurrencesMiddle Triassic — about 0 of 8 occurrencesLate Triassic — about 1 of 8 occurrencesLate TriassicEarly Jurassic — about 0 of 8 occurrencesMiddle Jurassic — about 0 of 8 occurrencesLate Jurassic — about 2 of 8 occurrencesEarly Cretaceous — about 0 of 8 occurrences476–465 Mya — about 0.4 occurrences465–453 Mya — about 0.6 occurrences453–442 Mya — about 0.2 occurrences442–431 Mya — about 1.0 occurrences431–420 Mya — about 3 occurrences240–229 Mya — about 0.8 occurrences229–217 Mya — about 0.2 occurrences150–139 Mya — about 2 occurrences458.2 Mya149.2 Mya476 Mya139 Mya

8 occurrences of Sipuncula on record, most of them in the Silurian. 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

8 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

6 formations

Solnhofen — 48.91°N, 11.14°EMosalem — 42.27°N, 90.42°WRacine — 41.65°N, 87.68°WMartuljek Limestone — 46.40°N, 13.84°ERacine Dolomite — 42.00°N, 88.00°WGilwern Volcanic — 52.24°N, 3.38°W

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The named rock units Sipuncula has been recovered from, largest first. Drawn where the rock is now, not where it formed. 1 occurrence has no formation on record, which is common for older literature.

Sipuncula and its relatives

Silurian

Where Sipuncula and its relatives were recorded in the Silurian.

Found in the same rock

141 taxa

The Paleobiology Database records 7 sites for Sipuncula, 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

5 references

Each of the 8 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. 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 Sipuncula

Credit
EcologyWA
Licence
CC0
Commercial use
the licence allows it

No 3D scan of Sipuncula 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 itSchizocoela through timeFormations of the SilurianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.