Exigua

Exigua is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived from 501 to 497 million years ago during the Dresbachian faunal stage of the late Cambrian Period. Exigua is only known from the central part of the headshield or cranidium, so free cheeks, thorax and pygidium are unknown.

Exigua

via iDigBio · via iDigBio. 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
PlethopeltidaePBDB
Diet
carnivorePBDB, for Trilobita
Life habit
low-level epifaunalPBDB, for Trilobita
Motility
fast-movingPBDB, for Trilobita
Vision
well-developedPBDB
Environment
marinePBDB, for Trilobita

Time the record covers

At least 2.5 million years on record.

The record covers at least 499.5 Mya to 497 Mya. No occurrence read is dated outside 504.5 Mya to 486.85 Mya.

Cambrian — about 6 of 6 occurrencesCambrianOrdovician — about 0 of 6 occurrences505–504 Mya — about 0.1 occurrences504–504 Mya — about 0.5 occurrences504–503 Mya — about 0.5 occurrences503–503 Mya — about 0.5 occurrences503–502 Mya — about 0.5 occurrences502–501 Mya — about 0.5 occurrences501–501 Mya — about 0.5 occurrences501–500 Mya — about 0.5 occurrences500–499 Mya — about 0.4 occurrences499–499 Mya — about 0.3 occurrences499–498 Mya — about 0.3 occurrences498–498 Mya — about 0.3 occurrences498–497 Mya — about 0.3 occurrences497–496 Mya — about 0.1 occurrences496–496 Mya — about 0.1 occurrences496–495 Mya — about 0.1 occurrences495–494 Mya — about 0.1 occurrences494–494 Mya — about 0.1 occurrences494–493 Mya — about 0.1 occurrences493–493 Mya — about 0.1 occurrences493–492 Mya — about 0.1 occurrences492–491 Mya — about 0.1 occurrences491–491 Mya — about 0.1 occurrences491–490 Mya — about 0.1 occurrences490–489 Mya — about 0.1 occurrences489–489 Mya — about 0.1 occurrences489–488 Mya — about 0.1 occurrences488–488 Mya — about 0.1 occurrences488–487 Mya — about 0.1 occurrences487–486 Mya — about 0.0 occurrences499.5 Mya497 Mya505 Mya486.4 Mya

6 occurrences of Exigua 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

6 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

Holm Dal — 82.42°N, 39.75°WSkeels Corner Slate — 44.78°N, 73.11°WOrr — 39.21°N, 113.32°W

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

Exigua and its relatives

Cambrian

Where Exigua and its relatives were recorded in the Cambrian.

Found in the same rock

66 taxa

The Paleobiology Database records 6 sites for Exigua, 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 6 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 Exigua

Source
iDigBio
Credit
via iDigBio
Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record

3D model

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

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 itPlethopeltidae through timeFormations of the CambrianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Howell 1937