Sphenacodon

Sphenacodon is an extinct genus of synapsid that lived from about 300 to about 280 million years ago (Ma) during the Late Carboniferous and Early Permian periods. Like the closely related Dimetrodon, Sphenacodon was a carnivorous member of the Eupelycosauria family Sphenacodontidae. However, Sphenacodon had a low crest along its back, formed from blade-like bones on its vertebrae instead of the tall dorsal sail found in Dimetrodon. Fossils of Sphenacodon are known from New Mexico and the Utah–Arizona border region in North America.

Sphenacodon

Smokeybjb · 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
SphenacodontinaePBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Amniota

Time the record covers

At least 5.3 million years on record.

The record covers at least 298.9 Mya to 293.52 Mya. No occurrence read is dated outside 307 Mya to 274.4 Mya.

Carboniferous — about 2 of 23 occurrencesCarboniferousPermian — about 21 of 23 occurrencesPermian308–307 Mya — about 0.0 occurrences307–305 Mya — about 0.0 occurrences305–304 Mya — about 0.0 occurrences304–303 Mya — about 0.2 occurrences303–302 Mya — about 0.4 occurrences302–301 Mya — about 0.4 occurrences301–300 Mya — about 0.4 occurrences300–299 Mya — about 0.8 occurrences299–297 Mya — about 2 occurrences297–296 Mya — about 2 occurrences296–295 Mya — about 2 occurrences295–294 Mya — about 2 occurrences294–293 Mya — about 2 occurrences293–292 Mya — about 2 occurrences292–291 Mya — about 2 occurrences291–290 Mya — about 2 occurrences290–288 Mya — about 2 occurrences288–287 Mya — about 2 occurrences287–286 Mya — about 2 occurrences286–285 Mya — about 0.4 occurrences285–284 Mya — about 0.2 occurrences284–283 Mya — about 0.1 occurrences283–282 Mya — about 0.1 occurrences282–281 Mya — about 0.1 occurrences281–279 Mya — about 0.1 occurrences279–278 Mya — about 0.1 occurrences278–277 Mya — about 0.1 occurrences277–276 Mya — about 0.1 occurrences276–275 Mya — about 0.1 occurrences275–274 Mya — about 0.0 occurrences298.9 Mya293.52 Mya307.7 Mya273.7 Mya

23 occurrences of Sphenacodon 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

23 occurrences

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

9 formations

Abo/Cutler — 36.18°N, 106.67°WAbo/Cutler — 35.72°N, 106.78°WAbo/Cutler — 36.16°N, 106.64°WAbo/Cutler — 34.17°N, 106.75°WEl Cobre Canyon — 36.16°N, 106.66°WEl Cobre Canyon — 36.14°N, 106.62°WAbo — 35.77°N, 106.69°WAbo — 34.64°N, 107.18°WCutler — 37.03°N, 110.06°WCutler — 36.16°N, 106.65°WCutler — 36.31°N, 106.35°WArroyo del Agua — 36.12°N, 106.66°WArroyo del Agua — 36.12°N, 106.64°WLaborcita — 33.08°N, 106.08°WKenilworth Sandstone — 52.38°N, 1.57°WSangre de Cristo — 34.64°N, 107.18°WHalgaito — 37.29°N, 109.86°W

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The named rock units Sphenacodon has been recovered from, largest first. Drawn where the rock is now, not where it formed.

Sphenacodon and its relatives

Permian

Where Sphenacodon and its relatives were recorded in the Permian.

Found in the same rock

67 taxa

The Paleobiology Database records 18 sites for Sphenacodon, 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

10 references

Each of the 23 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 Sphenacodon

Credit
Smokeybjb
Licence
CC BY-SA 3.0
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

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 itSphenacodontinae through timeFormations of the PermianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Marsh 1878