Orthoceratoidea
Orthoceratoidea, from Ancient Greek ὀρθός (orthós), meaning "straight", and κέρας (kéras), meaning "horn", is a major subclass of nautiloid cephalopods. Members of this subclass usually have orthoconic (straight) to slightly cyrtoconic (curved) shells, and central to subcentral siphuncles which may bear internal deposits. Orthoceratoids are also characterized by dorsomyarian muscle scars, extensive cameral deposits, and calciosiphonate connecting rings with a porous and calcitic inner layer.
Parent Géry · CC BY-SA 3.0 · 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
- CephalopodaPBDB
- Diet
- carnivorePBDB, for Cephalopoda
- Life habit
- nektonicPBDB, for Cephalopoda
- Motility
- fast-movingPBDB, for Cephalopoda
- Vision
- well-developedPBDB, for Cephalopoda
- Environment
- marinePBDB, for Cephalopoda
Time the record covers
At least 363 million years on record.
The record covers at least 483.4 Mya to 119.57 Mya. No occurrence read is dated outside 486.85 Mya to 113.2 Mya.
4,732 occurrences of Orthoceratoidea on record, most of them in the Ordovician. The Paleobiology Database records this as a living group, and the chart stops with its fossils rather than at the present. 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
4,732 occurrences- Ordovician47%
- Silurian19%
- Devonian11%
- Carboniferous12%
- Permian6%
- Early Triassic1%
- Middle Triassic2%
- Late Triassic1%
- Early Cretaceousunder 1%
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
802 formations
- Fluminimaggiore Formation154
- Graham Formation · Cisco Group82
- Baota Formation80
- Shan Majiagou Formation74
- Fayetteville Formation65
- Dunleith Formation · Galena Group52
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The named rock units Orthoceratoidea has been recovered from, largest first. Drawn where the rock is now, not where it formed. 778 further formations hold fewer occurrences each and are not listed. 702 occurrences have no formation on record, which is common for older literature.
Orthoceratoidea and its relatives
OrdovicianWhere Orthoceratoidea and its relatives were recorded in the Ordovician.
Found in the same rock
2,736 taxa- Orthoceras52 sites
- Ctenodonta44 sites
- Leptaena39 sites
- Crinoidea36 sites
- Lingula35 sites
- Hallopora34 sites
- Nuculites34 sites
- Michelinoceras33 sites
- Rafinesquina31 sites
- Flexicalymene30 sites
- Pterinea29 sites
- Sowerbyella29 sites
- Cornulites28 sites
- Isotelus28 sites
- Modiolopsis28 sites
- Conularia27 sites
- Platystrophia27 sites
- Camarotoechia26 sites
- Sinuites26 sites
- Remopleurides25 sites
- Schuchertella25 sites
- Spirifer25 sites
- Strophomena24 sites
- Ambonychia23 sites
The Paleobiology Database records at least 841 sites for Orthoceratoidea, and this reads 240 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
646 references- Biostratigraphy of the Middle and Late Ordovician cephalopods of the Upper Mississippi Valley area305
- Carboniferous Cephalopods of Arkansas225
- Ordovician cephalopod fauna of Baffin Island123
- Nautiloids before and during the ammonoid origin in a Siluro–Devonian section of the Tafilalt (Morocco)102
- Regional Stratigraphic Table of North China83
- Nautiloid assemblages from middle-late Silurian of southwestern Sardinia: a proposal81
- The surficial geology, paleontology, and paleoecology of the Finis Shale (Pennsylvanian, Lower Virgilian) in Jack County, Texas81
- Middle and Upper Ordovician nautiloid cephalopods of the Cincinnati Arch region of Kentucky, Indiana, and Ohio73
- Zonation of the Middle and Upper Ordovician strata in northwestern Georgia63
- Faunas from the Upper Silurian (Upper Ludlovian) in the Ludlow-Much Wenlock District, England51
- Stratigraphic Summary of the Southwestern Region of China51
- Revision of some common Carboniferous genera of North American orthocerid nautiloids49
Each of the 4,732 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. 634 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 Orthoceratoidea
- Source
- Wikipedia/Commons
- Credit
- Parent Géry
- Licence
- CC BY-SA 3.0
- Commercial use
- the licence allows it
No 3D scan of Orthoceratoidea 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 itCephalopoda through timeFormations of the OrdovicianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. (M'Coy 1844)