Dawsonoceratidae
Dawsonoceratidae is an extinct family of orthoconic nautiloid cephalopods that lived in what would be North America and Europe from the Late Ordovician through the Middle Devonian from about 480–390 mya, existing for approximately 90 million years.

Daderot · CC0 · 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
- OrthoceratinaPBDB
- Diet
- carnivorePBDB, for Orthocerida
- Life habit
- nektonicPBDB, for Orthocerida
- Motility
- actively mobilePBDB, for Orthocerida
- Vision
- well-developedPBDB, for Cephalopoda
- Environment
- marinePBDB, for Orthocerida
Time the record covers
At least 67 million years on record.
The record covers at least 461.1 Mya to 393.47 Mya. No occurrence read is dated outside 477.1 Mya to 383.4 Mya.
185 occurrences of Dawsonoceratidae on record, most of them in the Silurian. 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
185 occurrences- Ordovician39%
- Silurian57%
- Devonian4%
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
76 formations
- Racine Formation11
- Irondequoit Formation · Clinton Group11
- Rochester Formation · Clinton Group8
- Rochester Shale Formation · Clinton Group7
- Boda Limestone Formation7
- Maquoketa Formation6
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The named rock units Dawsonoceratidae has been recovered from, largest first. Drawn where the rock is now, not where it formed. 52 further formations hold fewer occurrences each and are not listed. 12 occurrences have no formation on record, which is common for older literature.
Dawsonoceratidae and its relatives
SilurianWhere Dawsonoceratidae and its relatives were recorded in the Silurian.
Found in the same rock
1,836 taxa- Dalmanites45 sites
- Dawsonoceras45 sites
- Atrypa reticularis44 sites
- Leptaena rhomboidalis41 sites
- Eospirifer radiatus39 sites
- Dawsonoceras annulatum36 sites
- Whitfieldella33 sites
- Atrypa31 sites
- Michelinoceras30 sites
- Calymene28 sites
- Eoplectodonta (Eoplectodonta) transversalis28 sites
- Metaspyroceras28 sites
- Orthoceras27 sites
- Schuchertella27 sites
- Dalmanella26 sites
- Favosites25 sites
- Pterinea25 sites
- Fenestella24 sites
- Brachyprion (Protomegastrophia) profunda23 sites
- Enterolasma23 sites
- Platyceras23 sites
- Anaspyroceras22 sites
- Fardenia (Coolinia)22 sites
- Stegerhynchus22 sites
The Paleobiology Database records 151 sites for Dawsonoceratidae, and this reads all of them. Of that, one read hit the database's own return limit, so every count below is a floor rather than a total. 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
51 references- Biostratigraphy of the Middle and Late Ordovician cephalopods of the Upper Mississippi Valley area43
- The Clinton of Western and Central New York28
- Revision of annulated orthoceridan cephalopods of the Baltoscandic Ordovician10
- Wenlockian fossil communities in New York State and adjacent areas: Paleontology and Paleoecology10
- The Silurian (Wenlockian) reef fauna of Southeastern Wisconsin8
- The cephalopods of Boda Limestone, Late Ordovocian, of Dalarna, Sweden7
- Caradocian-Gedinnian echinoderm associations of Central and Eastern North America7
- Silurian field excursions: Prague Basin (Barrandian), Bohemia6
- New data on the stratigraphy and correlation of the South - East Baltic Wenlockian and Ludlovian (Silurian)5
- Evidence for Palaeozoic orthoconic cephalopods with bimineralic shells4
- Ordovician and Silurian nautiloid cephalopods from Anticosti Island: traject across the Ordovician-Silurian (O-S) boundary4
- Trilobite assemblages of the North Atlantic Region2
Each of the 185 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. 39 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 Dawsonoceratidae
- Source
- Wikipedia/Commons
- Credit
- Daderot
- Licence
- CC0
- Commercial use
- the licence allows it
No 3D scan of Dawsonoceratidae 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 itOrthoceratina through timeFormations of the SilurianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Flower 1962