Ptyctodus
Ptyctodus is an extinct armour-plated fish of the late Devonian. Ptyctodus belongs to the family Ptyctodontidae and is of the class Placodermi. They share a close resemblance to modern day chimaeras (Holocephali). Fossils of this armour-plated fish have been found in locations such as in Russia, the Michigan Basis, and Arizona, United States.

Dunkleosteus_terrelli_2.jpg : Original uploader was Apokryltaros at en.wikipedia derivative work: Kev min § · CC BY 2.5 · 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
- PtyctodontidaePBDB
- Diet
- carnivorePBDB, for Placodermi
- Life habit
- nektonicPBDB, for Placodermi
- Motility
- actively mobilePBDB, for Placodermi
Time the record covers
At least 22 million years on record.
The record covers at least 387.95 Mya to 365.2 Mya. No occurrence read is dated outside 393.47 Mya to 358.86 Mya.
11 occurrences of Ptyctodus 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
11 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
7 formations
- Louisiana Limestone Formation3
- Dundee Limestone Formation · Colombus Group2
- Cedar Valley Formation1
- Dankov-Lebedyan Beds Formation1
- Oberer Plattenkalk Formation1
- Rockport Quarry Limestone Formation1
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The named rock units Ptyctodus 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.
Ptyctodus and its relatives
DevonianWhere Ptyctodus and its relatives were recorded in the Devonian.
Found in the same rock
122 taxa- Chonetes3 sites
- Spirifer3 sites
- Ambocoelia2 sites
- Conopoterium2 sites
- Cornulites2 sites
- Cyrtina2 sites
- Delthyris2 sites
- Dunkleosteus2 sites
- Glyptolepis2 sites
- Leioclema2 sites
- Leptalosia scintilla2 sites
- Microcyathus2 sites
- Neozaphrentis2 sites
- Nucleospira2 sites
- Onychodus2 sites
- Orbinaria pyxidata2 sites
- Osteolepididae2 sites
- Philhedra rowleyi2 sites
- Spirorbis2 sites
- Streblotrypa2 sites
- Tabulipora2 sites
- ? Rhopalonaria sp.1 site
- Acanthocrania spiculata1 site
- Acanthodes lopatini1 site
The Paleobiology Database records 11 sites for Ptyctodus, 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
6 references- An examination of the Devonian fishes of Michigan4
- Stratigraphy and fauna of the Louisiana Limestone of Missouri3
- End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates1
- Psammosteiforms (Agnatha, Heterostraci) from the Lower Frasnian of the Mikhailovskii Mine, Kursk Region, Russia1
- A new ptyctodont placoderm, Ptyctodopsis, from the Middle Devonian of Iowa1
- New Finds of Acanthodians, Arthrodires, Crossopterygians, Ganoids and Dipnoans in the Upper Middle Devonian Calcareous Flags (Oberer Plattenkalk) of the Bergisch Gladbach-Paffrath Trough (Part 1)1
Each of the 11 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 Ptyctodus
- Source
- Wikipedia/Commons
- Credit
- Dunkleosteus_terrelli_2.jpg : Original uploader was Apokryltaros at en.wikipedia derivative work: Kev min §
- Licence
- CC BY 2.5
- Commercial use
- the licence allows it
No 3D scan of Ptyctodus 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
- Source
- Wikipedia, “Ptyctodus”
- 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 itPtyctodontidae through timeFormations of the DevonianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Pander 1858