Pachyosteomorphi
Pachyosteomorphi is an extinct clade of arthrodire placoderms within the Eubrachythoraci, armored fish most diverse during the Devonian. Most are considered to be pelagic long-distance swimmers, leading to their widespread distribution beginning from at least the Middle Devonian period.

Apokryltaros · 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
- BrachythoraciPBDB
- Diet
- carnivorePBDB, for Arthrodira
- Life habit
- nektonicPBDB, for Arthrodira
- Motility
- actively mobilePBDB, for Arthrodira
Time the record covers
At least 28 million years on record.
The record covers at least 393.47 Mya to 365.2 Mya. No occurrence read is dated outside 399.5 Mya to 358.86 Mya.
57 occurrences of Pachyosteomorphi 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
57 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
30 formations
- Gogo Formation5
- Elm Point Formation · Elk Point Group3
- Ohio Shale Formation2
- Gauja Formation2
- Burtnieki Formation2
- Narva Formation2
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The named rock units Pachyosteomorphi has been recovered from, largest first. Drawn where the rock is now, not where it formed. 6 further formations hold fewer occurrences each and are not listed. 9 occurrences have no formation on record, which is common for older literature.
Pachyosteomorphi and its relatives
DevonianWhere Pachyosteomorphi and its relatives were recorded in the Devonian.
Found in the same rock
395 taxa- Glyptolepis15 sites
- Cheirolepis7 sites
- Onychodus7 sites
- Byssacanthus dilatatus6 sites
- Holonema6 sites
- Homostius latus6 sites
- Actinolepis tuberculata5 sites
- Asterolepis estonica5 sites
- Devononchus concinnus5 sites
- Dipnoi5 sites
- Dipterus5 sites
- Heterosteus ingens5 sites
- Dickosteus4 sites
- Diplacanthus4 sites
- Dunkleosteus4 sites
- Elmosteus lundarensis4 sites
- Ganosteus artus4 sites
- Gyroptychius pauli4 sites
- Holoptychiidae4 sites
- Laccognathus4 sites
- Orvikuina4 sites
- Plourdosteus4 sites
- Plourdosteus livonicus4 sites
- Tartuosteus4 sites
The Paleobiology Database records 44 sites for Pachyosteomorphi, 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
31 references- The Middle Devonian fishes of the Baltic States (Estonia, Latvia) and Belarus9
- End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates6
- Eubrachythoracid arthrodires from Gogo, Western Australia5
- An examination of the Devonian fishes of Michigan4
- Eastmanosteus lundarensis sp. nov. from the Middle Devonian Elm Point and Winnipegosis Formations of Manitoba4
- Late Devonian fossil fishes sites of Scotland2
- A new genus of arthrodires from the Upper Devonian of Timan2
- Monographie des poissons fossiles du vieux grés rouge : ou système Dévonien (Old red sandstone) des Iles Britanniques et de Russie / par L. Agassiz2
- A new aspinothoracid arthrodire from the Late Devonian of Ohio, U.S.A1
- A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China1
- Two new species of Dunkleosteus Lehman, 1956, from the Ohio Shale Formation (USA, Famennian) and the Kettle Point Formation (Canada, Upper Devonian), and a cladistic analysis of the Eubrachythoraci (Placodermi, Arthrodira)1
- Psammosteiforms (Agnatha, Heterostraci) from the Lower Frasnian of the Mikhailovskii Mine, Kursk Region, Russia1
Each of the 57 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. 19 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 Pachyosteomorphi
- Source
- Wikipedia/Commons
- Credit
- Apokryltaros
- Licence
- CC BY-SA 4.0
- Commercial use
- the licence allows it
No 3D scan of Pachyosteomorphi 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 itBrachythoraci through timeFormations of the DevonianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Stensiö 1944