Protocaris

Protocaris marshi is an extinct species of bivalved arthropod known from a single specimen collected from the Cambrian Series 2 aged Parker Formation from the Parker Quarry of northwestern Vermont, United States. The specimen is preserved in top-down view and has a bivalved carapace, a segmented trunk and a forked tail. Its precise taxonomic position is uncertain, due to the limited nature of known remains, but it is suggested to be a member of Hymenocarina belonging to the family Protocarididae, which also includes Tokummia and Branchiocaris.

Protocaris

Qohelet12 · 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
ArthropodaPBDB
Motility
actively mobilePBDB, for Arthropoda

Time the record covers

At most 8.8 million years on record.

Every occurrence read is dated to somewhere between 515.3 Mya and 506.5 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Cambrian — about 5 of 5 occurrencesCambrian515–515 Mya — about 0.1 occurrences515–515 Mya — about 0.2 occurrences515–514 Mya — about 0.2 occurrences514–514 Mya — about 0.3 occurrences514–514 Mya — about 0.3 occurrences514–514 Mya — about 0.3 occurrences514–513 Mya — about 0.3 occurrences513–513 Mya — about 0.3 occurrences513–513 Mya — about 0.3 occurrences513–512 Mya — about 0.3 occurrences512–512 Mya — about 0.3 occurrences512–512 Mya — about 0.3 occurrences512–511 Mya — about 0.3 occurrences511–511 Mya — about 0.3 occurrences511–511 Mya — about 0.3 occurrences511–510 Mya — about 0.3 occurrences510–510 Mya — about 0.3 occurrences510–510 Mya — about 0.2 occurrences510–509 Mya — about 0.0 occurrences509–509 Mya — about 0.0 occurrences509–509 Mya — about 0.0 occurrences509–508 Mya — about 0.0 occurrences508–508 Mya — about 0.0 occurrences508–508 Mya — about 0.0 occurrences508–507 Mya — about 0.0 occurrences507–507 Mya — about 0.0 occurrences507–507 Mya — about 0.0 occurrences507–506 Mya — about 0.0 occurrences515.8 Mya506 Mya

5 occurrences of Protocaris 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

5 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

Parker Slate — 44.48°N, 73.21°WParker Slate — 44.74°N, 73.16°WKinzers — 40.04°N, 76.31°WKinzers — 40.09°N, 76.35°WParker — 44.73°N, 73.15°W

Loading coastlines…

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

Protocaris and its relatives

Cambrian

Where Protocaris and its relatives were recorded in the Cambrian.

Found in the same rock

75 taxa

The Paleobiology Database records 5 sites for Protocaris, 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

3 references

Each of the 5 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 Protocaris

Credit
Qohelet12
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan of Protocaris was found in MorphoSource and Sketchfab.

Smithsonian Open Access was 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 itArthropoda through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.