Thecodontia

Thecodontia, now considered an obsolete taxonomic grouping, was formerly used to describe a diverse "order" of early archosaurian reptiles that first appeared in the latest Permian period and flourished until the end of the Triassic period. All of them were built somewhat like crocodiles but with shorter skulls, more erect pose and usually somewhat lighter. The group includes the ancestors of dinosaurs, pterosaurs, and crocodilians, as well as a number of extinct forms that did not give rise to any descendants. The term thecodont is still used as an anatomical description of the tooth morphology seen in these species and others.

Thecodontia

Dmitry Bogdanov · 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
ArchosauriaPBDB
Diet
carnivorePBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Diapsida

Time the record covers

At least 45 million years on record.

The record covers at least 247 Mya to 201.4 Mya. No occurrence read is dated outside 251.902 Mya to 174.7 Mya.

Permian — about 0 of 25 occurrencesEarly Triassic — about 4 of 25 occurrencesMiddle Triassic — about 13 of 25 occurrencesMiddle TriassicLate Triassic — about 6 of 25 occurrencesLate TriassicEarly Jurassic — about 2 of 25 occurrencesEarly JurassicMiddle Jurassic — about 0 of 25 occurrences253–251 Mya — about 0.5 occurrences251–248 Mya — about 2 occurrences248–245 Mya — about 5 occurrences245–243 Mya — about 6 occurrences243–240 Mya — about 3 occurrences240–237 Mya — about 0.3 occurrences237–235 Mya — about 1 occurrence235–232 Mya — about 1 occurrence232–229 Mya — about 1 occurrence229–227 Mya — about 1.0 occurrences227–224 Mya — about 0.2 occurrences224–221 Mya — about 0.2 occurrences221–219 Mya — about 0.2 occurrences219–216 Mya — about 0.2 occurrences216–213 Mya — about 0.2 occurrences213–211 Mya — about 0.2 occurrences211–208 Mya — about 0.2 occurrences208–205 Mya — about 0.2 occurrences203–200 Mya — about 0.2 occurrences200–197 Mya — about 0.4 occurrences197–195 Mya — about 0.4 occurrences195–192 Mya — about 0.3 occurrences192–189 Mya — about 0.1 occurrences189–187 Mya — about 0.1 occurrences187–184 Mya — about 0.1 occurrences184–181 Mya — about 0.1 occurrences181–179 Mya — about 0.1 occurrences179–176 Mya — about 0.1 occurrences176–173 Mya — about 0.0 occurrences247 Mya201.4 Mya253 Mya173 Mya

25 occurrences of Thecodontia on record, most of them in the Middle Triassic. The Paleobiology Database records this as a living group, and the chart stops with its fossils rather than at the present. 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

25 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

10 formations

Ermaying — 39.00°N, 112.30°EErmaying — 36.97°N, 112.85°EErmaying — 36.92°N, 112.90°EErmaying — 36.98°N, 112.87°EErmaying — 37.07°N, 113.02°EDonguz — 51.36°N, 55.31°EDonguz — 52.53°N, 53.50°ERöt — 48.53°N, 8.59°ERöt — 48.45°N, 8.42°EZhenzhuchong — 27.00°N, 107.00°ELossiemouth Sandstone — 57.72°N, 3.29°WElliot — 29.13°S, 27.37°ETecovas — 34.96°N, 101.70°WHardegsen — 51.59°N, 10.12°EAgua de la Zorra — 32.68°S, 69.36°WPetropavlovskaya — 52.15°N, 55.89°E

Loading coastlines…

The named rock units Thecodontia has been recovered from, largest first. Drawn where the rock is now, not where it formed. 6 occurrences have no formation on record, which is common for older literature.

Thecodontia and its relatives

Middle Triassic

Where Thecodontia and its relatives were recorded in the Middle Triassic.

Found in the same rock

76 taxa

The Paleobiology Database records 25 sites for Thecodontia, 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

14 references

Each of the 25 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. 2 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 Thecodontia

Credit
Dmitry Bogdanov
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 itArchosauria through timeFormations of the Middle TriassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. (Owen 1859)