Isorophida

Isorophida is an extinct order of prehistoric echinoderms in the class Edrioasteroidea. Isorophids are characterized by a disc-shaped, dome-shaped or club-shaped theca with ambulacra typically limited to the upward-facing oral surface which is bordered by an peripheral rim that flares outward parallel to the substrate. The aboral (substrate-facing) surface is unplated.

Isorophida

Sharman, G. and Newton, Edwin Tulley · Public Domain · 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
EdrioasteroideaPBDB
Diet
suspension feederPBDB, for Edrioasteroidea
Life habit
low-level epifaunalPBDB, for Edrioasteroidea
Motility
stationary, attached, epibiontPBDB, for Edrioasteroidea
Vision
limitedPBDB, for Edrioasteroidea
Environment
marinePBDB, for Echinodermata

Time the record covers

At least 221 million years on record.

The record covers at least 504.5 Mya to 283.3 Mya. No occurrence read is dated outside 508.2 Mya to 274.4 Mya.

Cambrian — about 5 of 140 occurrencesCambrianOrdovician — about 96 of 140 occurrencesOrdovicianSilurian — about 14 of 140 occurrencesSilurianDevonian — about 12 of 140 occurrencesDevonianCarboniferous — about 12 of 140 occurrencesCarboniferousPermian — about 1 of 140 occurrencesPermian513–505 Mya — about 0.9 occurrences505–497 Mya — about 2 occurrences497–489 Mya — about 2 occurrences480–472 Mya — about 4 occurrences472–464 Mya — about 2 occurrences464–456 Mya — about 10 occurrences456–448 Mya — about 57 occurrences448–440 Mya — about 25 occurrences440–432 Mya — about 3 occurrences432–424 Mya — about 8 occurrences424–416 Mya — about 2 occurrences416–408 Mya — about 3 occurrences408–399 Mya — about 2 occurrences399–391 Mya — about 1 occurrence391–383 Mya — about 3 occurrences383–375 Mya — about 0.8 occurrences375–367 Mya — about 0.7 occurrences367–359 Mya — about 0.7 occurrences359–351 Mya — about 1 occurrence351–343 Mya — about 0.9 occurrences343–335 Mya — about 2 occurrences335–326 Mya — about 3 occurrences326–318 Mya — about 4 occurrences318–310 Mya — about 0.6 occurrences310–302 Mya — about 0.4 occurrences286–278 Mya — about 0.6 occurrences278–270 Mya — about 0.4 occurrences504.5 Mya283.3 Mya513 Mya270 Mya

140 occurrences of Isorophida on record, most of them in the Ordovician. 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

59 formations

Bromide — 34.00°N, 97.00°WBromide — 34.07°N, 97.17°WBromide — 34.03°N, 97.17°WIon — 42.00°N, 90.50°WDunleith — 42.00°N, 90.50°WDunleith — 43.49°N, 91.87°WUpper Fezouata — 30.42°N, 5.85°WUpper Fezouata — 30.57°N, 5.99°WUpper Fezouata — 30.55°N, 5.68°WOrchard Creek Shale — 37.19°N, 89.45°WFairview — 39.00°N, 84.00°WDecorah Shale — 44.00°N, 92.00°WScales — 37.23°N, 89.47°WGolf Course — 33.95°N, 97.12°WVerulam — 44.75°N, 79.33°WVerulam — 44.50°N, 79.17°WVerulam — 44.00°N, 79.00°WKope — 39.00°N, 84.00°WBellevue — 39.00°N, 84.00°WWhitewater — 39.00°N, 84.00°WBobcaygeon — 44.56°N, 78.98°WBobcaygeon — 44.53°N, 78.55°WBangor Limestone — 34.59°N, 87.63°WRochester Shale — 43.10°N, 79.06°WRochester Shale — 43.17°N, 78.68°WQuimbys Mill — 42.00°N, 90.50°WSpechts Ferry — 42.00°N, 90.50°WGuttenberg — 42.00°N, 90.50°WLower Ktaoua — 30.00°N, 8.50°WLower Ktaoua — 31.21°N, 4.82°WLower Ktaoua — 31.37°N, 5.47°WUpper Tiouririne — 31.30°N, 5.23°WUpper Tiouririne — 31.54°N, 4.76°WJunkerberg — 50.44°N, 6.65°ECorryville — 39.00°N, 84.00°WWaynesville — 39.00°N, 84.00°W

Loading coastlines…

The named rock units Isorophida has been recovered from, largest first. Drawn where the rock is now, not where it formed. 35 further formations hold fewer occurrences each and are not listed. 8 occurrences have no formation on record, which is common for older literature.

Isorophida and its relatives

Ordovician

Where Isorophida and its relatives were recorded in the Ordovician.

Found in the same rock

1,564 taxa

The Paleobiology Database records 86 sites for Isorophida, 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

47 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. 35 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 Isorophida

Credit
Sharman, G. and Newton, Edwin Tulley
Licence
Public Domain
Commercial use
the licence allows it

No 3D scan of Isorophida 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 itEdrioasteroidea through timeFormations of the OrdovicianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0.