Cheloniellida

Cheloniellida is a taxon of extinct Paleozoic arthropods. As of 2018, 7 monotypic genera of cheloniellids had been formally described, whose fossils are found in marine strata ranging from Ordovician to Devonian in age. Cheloniellida has a controversial phylogenetic position, with previous studies associated it as either a member or relative of various fossil and extant arthropod taxa. It was later accepted as a member of Vicissicaudata within Artiopoda.

Cheloniellida

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
VicissicaudataPBDB
Motility
actively mobilePBDB, for Arthropoda

Time the record covers

At least 46 million years on record.

The record covers at least 457.2 Mya to 410.62 Mya. No occurrence read is dated outside 463.3 Mya to 399.5 Mya.

Ordovician — about 4 of 7 occurrencesOrdovicianSilurian — about 2 of 7 occurrencesSilurianDevonian — about 1 of 7 occurrencesDevonian465–462 Mya — about 0.5 occurrences462–460 Mya — about 1 occurrence460–458 Mya — about 1 occurrence458–456 Mya — about 0.4 occurrences454–451 Mya — about 0.2 occurrences451–449 Mya — about 0.3 occurrences449–447 Mya — about 0.3 occurrences447–445 Mya — about 0.2 occurrences440–438 Mya — about 0.1 occurrences438–436 Mya — about 0.4 occurrences436–434 Mya — about 0.4 occurrences434–431 Mya — about 0.1 occurrences427–425 Mya — about 0.5 occurrences425–423 Mya — about 0.5 occurrences411–409 Mya — about 0.1 occurrences409–407 Mya — about 0.2 occurrences407–405 Mya — about 0.2 occurrences405–403 Mya — about 0.2 occurrences403–400 Mya — about 0.2 occurrences400–398 Mya — about 0.1 occurrences457.2 Mya410.62 Mya465 Mya398 Mya

7 occurrences of Cheloniellida on record, most of them in the Ordovician. 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

7 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

5 formations

Letna — 50.00°N, 14.00°ESlot Burn — 55.65°N, 3.92°WHunsrück Slate — 49.83°N, 7.37°EBrandon Bridge — 43.03°N, 88.21°WZhaolaoyu — 35.00°N, 109.20°E

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The named rock units Cheloniellida has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Cheloniellida and its relatives

Ordovician

Where Cheloniellida and its relatives were recorded in the Ordovician.

Found in the same rock

339 taxa

The Paleobiology Database records 5 sites for Cheloniellida, 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 7 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 Cheloniellida

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

No 3D scan was found. Smithsonian Open Access, MorphoSource and Sketchfab were all searched.

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 itVicissicaudata through timeFormations of the OrdovicianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Broili 1932