Helicoplacus

Helicoplacus is the earliest well-studied fossil echinoderm. Fossil plates are known from several regions. Complete specimens were found in Lower Cambrian strata of the White Mountains of California.

Helicoplacus

Jonathan Chen · 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
HelicoplacidaePBDB
Diet
suspension feederPBDB
Life habit
epifaunalPBDB
Motility
stationary, attachedPBDB
Vision
blindPBDB, for Helicoplacoidea
Environment
marinePBDB, for Echinodermata

Time the record covers

At most 5.6 million years on record.

Every occurrence read is dated to somewhere between 515.3 Mya and 509.7 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Cambrian — about 2 of 2 occurrencesCambrian515–515 Mya — about 0.1 occurrences515–515 Mya — about 0.1 occurrences515–515 Mya — about 0.1 occurrences515–514 Mya — about 0.1 occurrences514–514 Mya — about 0.1 occurrences514–514 Mya — about 0.1 occurrences514–514 Mya — about 0.1 occurrences514–514 Mya — about 0.1 occurrences514–513 Mya — about 0.1 occurrences513–513 Mya — about 0.1 occurrences513–513 Mya — about 0.1 occurrences513–513 Mya — about 0.1 occurrences513–513 Mya — about 0.1 occurrences513–512 Mya — about 0.1 occurrences512–512 Mya — about 0.1 occurrences512–512 Mya — about 0.1 occurrences512–512 Mya — about 0.1 occurrences512–511 Mya — about 0.1 occurrences511–511 Mya — about 0.1 occurrences511–511 Mya — about 0.1 occurrences511–511 Mya — about 0.1 occurrences511–511 Mya — about 0.1 occurrences511–510 Mya — about 0.1 occurrences510–510 Mya — about 0.1 occurrences510–510 Mya — about 0.1 occurrences510–510 Mya — about 0.1 occurrences515.8 Mya509.2 Mya

2 occurrences of Helicoplacus on record, most of them in the Cambrian. 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

2 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

1 formation

Poleta — 37.30°N, 118.15°W

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

Helicoplacus and its relatives

Cambrian

Where Helicoplacus and its relatives were recorded in the Cambrian.

Found in the same rock

6 taxa

The Paleobiology Database records 2 sites for Helicoplacus, and this reads all of them. The number is how many of those sites it was catalogued from too.

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

2 references

Each of the 2 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 content2

Picture of Helicoplacus

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

3D model

Source
Sketchfab
Licence
CC Attribution
Commercial use
cannot be read from the licence given — check the record

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 itHelicoplacidae through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Durham and Caster 1963