Symmorium

Symmorium is an extinct symmoriiform cartilaginous fish from the Devonian and Carboniferous of the United States (Illinois) and Russia. The type species, Symmorium reniforme, was named by Edward Drinker Cope in 1893, with other species assigned to the genus having since been reclassified into other genera such as Petalodus. Symmorium bears close similarity in size and appearance to Stethacanthus but lacks the "spine-brush complex" in place of the first dorsal fin. Some paleontologists think that the two forms represented the males and females of related species, while other scientists think they were distinct genera.

Symmorium

Jonathan Chen · 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
SymmoriidaePBDB
Diet
carnivorePBDB, for Symmoriiformes
Life habit
nektonicPBDB, for Symmoriiformes
Motility
actively mobilePBDB, for Symmoriiformes

Time the record covers

At least 61 million years on record.

The record covers at least 365.2 Mya to 303.7 Mya. No occurrence read is dated outside 372.15 Mya to 298.9 Mya.

Devonian — about 2 of 4 occurrencesDevonianCarboniferous — about 2 of 4 occurrencesCarboniferousPermian — about 0 of 4 occurrences374–371 Mya — about 0.1 occurrences371–369 Mya — about 0.2 occurrences369–366 Mya — about 0.9 occurrences366–363 Mya — about 0.4 occurrences363–361 Mya — about 0.2 occurrences361–358 Mya — about 0.2 occurrences315–313 Mya — about 0.3 occurrences313–310 Mya — about 0.3 occurrences310–308 Mya — about 0.3 occurrences308–305 Mya — about 0.1 occurrences305–303 Mya — about 0.2 occurrences303–300 Mya — about 0.5 occurrences300–297 Mya — about 0.2 occurrences365.2 Mya303.7 Mya374 Mya297 Mya

4 occurrences of Symmorium 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

4 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

Linton — 40.94°N, 90.27°WWild Cow — 34.95°N, 106.30°WDankov-Lebedyan Beds — 52.97°N, 36.07°E

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The named rock units Symmorium has been recovered from, largest first. Drawn where the rock is now, not where it formed. 1 occurrence has no formation on record, which is common for older literature.

Symmorium and its relatives

Devonian

Where Symmorium and its relatives were recorded in the Devonian.

Found in the same rock

47 taxa

The Paleobiology Database records 4 sites for Symmorium, 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

4 references

Each of the 4 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 Symmorium

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

No 3D scan of Symmorium 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 itSymmoriidae through timeFormations of the DevonianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Cope 1893