Dimacrodon
Dimacrodon is an extinct genus of non-mammalian synapsid from the latest Early Permian San Angelo Formation of Texas. It is distinguished by toothless, possibly beaked jaw tips, large lower canines and a thin bony crest on top of its head. Previously thought to be an anomodont therapsid related to dicynodonts, it was later found to lack any diagnostic features of anomodonts or even therapsids and instead appears to be a 'pelycosaur'-grade synapsid of uncertain classification.

Ghedoghedo · 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
- DimacrodontidaePBDB
- Diet
- herbivorePBDB, for Anomodontia
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- terrestrialPBDB, for Amniota
Time the record covers
At most 17 million years on record.
Every occurrence read is dated to somewhere between 283.3 Mya and 266.9 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.
2 occurrences of Dimacrodon on record, most of them in the Permian. 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
2 occurrences- Permian100%
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
1 formation
- San Angelo Formation · Pease River Group2
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The named rock units Dimacrodon has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Dimacrodon and its relatives
PermianWhere Dimacrodon and its relatives were recorded in the Permian.
Found in the same rock
The Paleobiology Database records no fossil sites for Dimacrodon, so there is nothing to compare it with.
Entered from
2 references- Late Permian terrestrial vertebrates, U.S.A. and U.S.S.R1
- The San Angelo Formation, Permian of Texas, and its Vertebrates1
Each of the 2 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. Each entry links to doi.org. Relayed as the Paleobiology Database holds them, not checked against what they resolve to.
Media and terms
Media content1
Picture of Dimacrodon
- Source
- Wikipedia/Commons
- Credit
- Ghedoghedo
- Licence
- CC BY-SA 4.0
- Commercial use
- the licence allows it
No 3D scan was found. Smithsonian Open Access, MorphoSource and Sketchfab were all searched.
The description on this site
- Source
- Wikipedia, “Dimacrodon”
- 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 itDimacrodontidae through timeFormations of the PermianThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Olson and Beerbower 1953