Acernaspis

Acernaspis is an extinct genus of trilobite that is known from the Silurian. It contains two species, A. elliptifrons, and A. salmoensis. It is sometimes found preserved in burrows of various forms, sometimes in association with multiple moults, suggesting that it used tunnels as refuges whilst in its vulnerable moulting stage.

Acernaspis

Bloopityboop · 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
PhacopidaePBDB
Diet
carnivorePBDB, for Phacopina
Life habit
low-level epifaunalPBDB, for Trilobita
Motility
fast-movingPBDB, for Trilobita
Vision
well-developedPBDB, for Phacopidae
Environment
marinePBDB, for Trilobita

Time the record covers

At least 4.5 million years on record.

The record covers at least 443.1 Mya to 438.6 Mya. No occurrence read is dated outside 449.5 Mya to 426.7 Mya.

Ordovician — about 4 of 140 occurrencesOrdovicianSilurian — about 136 of 140 occurrencesSilurian450–449 Mya — about 0.1 occurrences449–448 Mya — about 0.4 occurrences448–448 Mya — about 0.4 occurrences448–447 Mya — about 0.4 occurrences447–446 Mya — about 0.4 occurrences446–445 Mya — about 0.4 occurrences445–444 Mya — about 0.8 occurrences444–444 Mya — about 0.9 occurrences444–443 Mya — about 3 occurrences443–442 Mya — about 7 occurrences442–441 Mya — about 7 occurrences441–440 Mya — about 7 occurrences440–440 Mya — about 21 occurrences440–439 Mya — about 21 occurrences439–438 Mya — about 13 occurrences438–437 Mya — about 9 occurrences437–437 Mya — about 9 occurrences437–436 Mya — about 9 occurrences436–435 Mya — about 9 occurrences435–434 Mya — about 9 occurrences434–433 Mya — about 9 occurrences433–433 Mya — about 5 occurrences433–432 Mya — about 0.0 occurrences432–431 Mya — about 0.0 occurrences431–430 Mya — about 0.0 occurrences430–429 Mya — about 0.0 occurrences429–429 Mya — about 0.0 occurrences429–428 Mya — about 0.0 occurrences428–427 Mya — about 0.0 occurrences427–426 Mya — about 0.0 occurrences443.1 Mya438.6 Mya450 Mya426.2 Mya

140 occurrences of Acernaspis on record, most of them in the Silurian. 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

140 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

33 formations

Jupiter — 49.47°N, 63.62°WJupiter — 49.38°N, 63.60°WJupiter — 49.47°N, 63.12°WJupiter — 49.38°N, 63.51°WJupiter — 49.56°N, 63.35°WJupiter — 49.38°N, 63.40°WJupiter — 49.35°N, 63.25°WJupiter — 49.25°N, 62.29°WJupiter — 49.25°N, 62.29°WJupiter — 49.22°N, 62.24°WJupiter — 49.15°N, 62.20°WJupiter — 49.24°N, 62.39°WJupiter — 49.14°N, 62.36°WJupiter — 49.13°N, 62.29°WJupiter — 49.23°N, 62.55°WJupiter — 49.23°N, 62.60°WJupiter — 49.48°N, 63.16°WJupiter — 49.43°N, 63.12°WBecscie — 49.80°N, 64.42°WBecscie — 49.61°N, 63.42°WBecscie — 49.56°N, 63.35°WBecscie — 49.61°N, 63.45°WBecscie — 49.38°N, 62.46°WBecscie — 49.66°N, 63.22°WGun River — 49.57°N, 63.38°WGun River — 49.38°N, 62.46°WGun River — 49.34°N, 62.43°WGun River — 49.53°N, 63.54°WGun River — 49.25°N, 62.38°WGun River — 49.19°N, 61.72°WWhite Head — 48.53°N, 64.33°WWhite Head — 46.88°N, 60.35°WWether Law Linn — 55.81°N, 3.37°WRichea Siltstone — 43.00°S, 146.00°ERichea Siltstone — 42.59°S, 146.41°EMulloch Hill — 55.28°N, 4.74°WVtorye Utyosy — 51.23°N, 84.79°ECape Schuchert — 77.51°N, 66.65°WCape Schuchert — 81.00°N, 65.00°WHughley Shales — 52.67°N, 2.00°WDamery Beds — 51.88°N, 2.23°WDamery Beds — 52.67°N, 2.00°WGasworks Sandstone — 52.67°N, 2.00°WSkelgill — 52.67°N, 2.00°WGun River or Goeland — 49.24°N, 62.48°WWoodland — 55.22°N, 4.88°WNewlands Farm — 55.28°N, 4.74°WLower Camregan Grits — 55.28°N, 4.74°WLower Camregan Grits — 55.24°N, 4.79°WWood Burn Grits — 55.25°N, 4.76°WMoyerokan — 67.31°N, 103.83°EMoyerokan — 67.34°N, 104.10°EKochumdek — 49.40°N, 136.38°EHaverford Mudstone — 51.82°N, 4.97°WDobele — 57.75°N, 22.58°EZelkovice — 50.00°N, 14.05°ESaelabonn — 60.17°N, 10.30°E

Loading coastlines…

The named rock units Acernaspis has been recovered from, largest first. Drawn where the rock is now, not where it formed. 9 further formations hold fewer occurrences each and are not listed. 7 occurrences have no formation on record, which is common for older literature.

Acernaspis and its relatives

Silurian

Where Acernaspis and its relatives were recorded in the Silurian.

Found in the same rock

566 taxa

The Paleobiology Database records 130 sites for Acernaspis, 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

28 references

Each of the 140 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. 16 further references are not listed. 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 Acernaspis

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

No 3D scan of Acernaspis was found in Sketchfab.

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 itPhacopidae through timeFormations of the SilurianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Campbell 1967