Protopteraspis

Protopteraspis is an extinct genus of pteraspidid heterostracan agnathan with fossils known from Lower Devonian marine strata in Western Europe. The animal's somewhat flat build has led some to believe that it was a bottom dweller, living in freshwater areas. It has been described as "somewhat unspecialized". Its snout was round and narrow, shorter than that of its immediate relatives. Protopteraspis also did not possess the cornua (horns) found on the headshields of other pterapsids; rather, it had "small points" behind the gill opening. It did possess a "medium-sized" dorsal spine. Plates covering the headshield had ridges of dentine. It is theorized that the headshield formed in youth and that it grew via growth of the plates, which fused in adulthood. The scales of the animal were "small and diamond shaped".

Protopteraspis

Apokryltaros · 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
ProtopteraspididaePBDB
Motility
actively mobilePBDB, for Chordata

Time the record covers

At most 6.6 million years on record.

Every occurrence read is dated to somewhere between 419.62 Mya and 413.02 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Silurian — about 0 of 33 occurrencesDevonian — about 33 of 33 occurrencesDevonian420–420 Mya — about 0.1 occurrences420–419 Mya — about 2 occurrences419–419 Mya — about 2 occurrences419–419 Mya — about 2 occurrences419–419 Mya — about 2 occurrences419–418 Mya — about 2 occurrences418–418 Mya — about 2 occurrences418–418 Mya — about 2 occurrences418–418 Mya — about 2 occurrences418–417 Mya — about 2 occurrences417–417 Mya — about 2 occurrences417–417 Mya — about 2 occurrences417–417 Mya — about 0.7 occurrences417–416 Mya — about 0.5 occurrences416–416 Mya — about 0.5 occurrences416–416 Mya — about 0.5 occurrences416–416 Mya — about 0.5 occurrences416–415 Mya — about 0.5 occurrences415–415 Mya — about 0.5 occurrences415–415 Mya — about 0.5 occurrences415–415 Mya — about 0.5 occurrences415–414 Mya — about 0.5 occurrences414–414 Mya — about 0.5 occurrences414–414 Mya — about 0.5 occurrences414–414 Mya — about 0.5 occurrences414–413 Mya — about 0.5 occurrences413–413 Mya — about 0.5 occurrences413–413 Mya — about 0.0 occurrences420.1 Mya412.5 Mya

33 occurrences of Protopteraspis on record, most of them in the Devonian. 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

33 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

8 formations

Psammosteus Limestone — 52.53°N, 2.48°WPsammosteus Limestone — 52.50°N, 2.62°WPsammosteus Limestone — 52.42°N, 2.72°WPsammosteus Limestone — 52.39°N, 2.63°WPsammosteus Limestone — 52.37°N, 2.54°WPsammosteus Limestone — 52.41°N, 2.32°WPsammosteus Limestone — 52.34°N, 2.39°WPsammosteus Limestone — 52.09°N, 2.87°WPsammosteus Limestone — 52.17°N, 2.44°WPsammosteus Limestone — 52.15°N, 2.73°WPsammosteus Limestone — 51.94°N, 3.40°WPsammosteus Limestone — 51.71°N, 2.51°WFraenkelryggen — 79.83°N, 12.00°EFraenkelryggen — 79.67°N, 12.37°EBen Nevis — 79.63°N, 12.29°EKnoydart — 45.62°N, 61.97°WLievin — 50.42°N, 2.77°EPod''emnaya — 79.50°N, 96.00°EDrake Bay — 73.44°N, 101.29°WRivieratoppen — 79.62°N, 12.75°E

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

Protopteraspis and its relatives

Devonian

Where Protopteraspis and its relatives were recorded in the Devonian.

Found in the same rock

117 taxa

The Paleobiology Database records 33 sites for Protopteraspis, 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

7 references

Each of the 33 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 Protopteraspis

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

No 3D scan of Protopteraspis 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 itProtopteraspididae through timeFormations of the DevonianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Leriche 1924