Poraspis
Searched as Poraspis siemiradzkii. The Paleobiology Database treats Poraspis as the accepted name.
Poraspis is an extinct genus of heterostracan. Fossils are found in Late Silurian and Early Devonian marine strata of Norway, Canada and the United States.

Lycaon.cl · CC BY-SA 3.0 · via Wikidata/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
- PoraspidinaePBDB
- Motility
- actively mobilePBDB, for Chordata
Time the record covers
At most 6.6 million years on record.
The one occurrence read is dated to somewhere between 419.62 Mya and 413.02 Mya, which is a dating window rather than a span.
1 occurrence of Poraspis 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
1 occurrences- Devonian100%
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
1 formation
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The named rock units Poraspis has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Poraspis and its relatives
DevonianWhere Poraspis and its relatives were recorded in the Devonian.
Found in the same rock
205 taxa- Corvaspis11 sites
- Cephalaspis9 sites
- Nikolivia elongata9 sites
- Turinia pagei9 sites
- Traquairaspis7 sites
- Protopteraspis6 sites
- Nostolepis5 sites
- Pteraspididae5 sites
- Turinia polita5 sites
- Acanthodii4 sites
- Anglaspis4 sites
- Boreania minima4 sites
- Dinaspidella4 sites
- Heterostraci4 sites
- Homalaspidella4 sites
- Nikolivia depressa4 sites
- Pionaspis amplissima4 sites
- Apalolepis brotzeni3 sites
- Apalolepis obruchevi3 sites
- Canonia grossi3 sites
- Ctenaspis3 sites
- Machairaspis3 sites
- Nikolivia gutta3 sites
- Nikolivia oervigi3 sites
The Paleobiology Database records 29 sites for Poraspis, 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
1 referenceEach of the 1 occurrence 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. Each entry links to doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content1

Picture of Poraspis
- Source
- Wikidata/Commons
- Credit
- Lycaon.cl
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
No 3D scan of Poraspis was found in Smithsonian Open Access and Sketchfab.
MorphoSource was not reached for this taxon, so this list is what the others held rather than everything there is.
The description on this site
- Source
- Wikipedia, “Poraspis”
- 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 itPoraspidinae through timeFormations of the DevonianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Kiaer 1932