Helmetia

Helmetia is an extinct genus of arthropods from the middle Cambrian (Wuliuan). Fossils of the type species Helmetia expansa have been found in the Burgess Shale of Canada. It is characterized by a pair of spines in front of its head. It is classified under Conciliterga, a group of trilobitomorph artiopod.

Helmetia

Jean-Bernard Caron · 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
ConcilitergaPBDB
Diet
carnivorePBDB
Life habit
nektobenthicPBDB
Motility
actively mobilePBDB
Vision
well-developedPBDB

Time the record covers

At most 15 million years on record.

Every occurrence read is dated to somewhere between 514.5 Mya and 499.5 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Cambrian — about 4 of 4 occurrencesCambrian515–514 Mya — about 0.0 occurrences514–514 Mya — about 0.1 occurrences514–513 Mya — about 0.1 occurrences513–513 Mya — about 0.1 occurrences513–512 Mya — about 0.1 occurrences512–512 Mya — about 0.1 occurrences512–511 Mya — about 0.1 occurrences511–511 Mya — about 0.1 occurrences511–510 Mya — about 0.1 occurrences510–510 Mya — about 0.1 occurrences510–509 Mya — about 0.3 occurrences509–509 Mya — about 0.3 occurrences509–508 Mya — about 0.3 occurrences508–508 Mya — about 0.4 occurrences508–507 Mya — about 0.4 occurrences507–506 Mya — about 0.4 occurrences506–506 Mya — about 0.3 occurrences506–505 Mya — about 0.3 occurrences505–505 Mya — about 0.1 occurrences505–504 Mya — about 0.1 occurrences504–504 Mya — about 0.1 occurrences504–503 Mya — about 0.1 occurrences503–503 Mya — about 0.1 occurrences503–502 Mya — about 0.1 occurrences502–502 Mya — about 0.1 occurrences502–501 Mya — about 0.1 occurrences501–501 Mya — about 0.1 occurrences501–500 Mya — about 0.1 occurrences500–500 Mya — about 0.1 occurrences500–499 Mya — about 0.0 occurrences515 Mya499 Mya

4 occurrences of Helmetia 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

4 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

3 formations

Burgess Shale — 51.44°N, 116.47°WBurgess Shale — 51.38°N, 116.43°WJince — 49.78°N, 13.97°EBalang — 28.42°N, 109.42°E

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

Helmetia and its relatives

Cambrian

Where Helmetia and its relatives were recorded in the Cambrian.

Found in the same rock

199 taxa

The Paleobiology Database records 3 sites for Helmetia, 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

4 references

Each of the 4 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 Helmetia

Credit
Jean-Bernard Caron
Licence
CC0
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 itConciliterga through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Walcott 1918