Prozostrodontia

Prozostrodontia is a clade of cynodonts including mammaliaforms and their closest relatives such as Tritheledontidae and Tritylodontidae. It was erected as a node-based taxon by Liu and Olsen (2010) and defined as the least inclusive clade containing Prozostrodon brasiliensis, Tritylodon langaevus, Pachygenelus monus, and Mus musculus. Prozostrodontia is diagnosed by several characters, including:Reduced prefrontal and postorbital bones, with the disappearance of a strut of bone called the postorbital bar separating the eye socket from the temporal region Unfused symphysis between the dentary bones in the lower jaw The presence of a small hole within the eye socket called the sphenopalatine foramen A long sagittal crest extending to the rearmost part of the lambdoidal crest at the back of the skull Neural spines of the dorsal vertebrae angled backward A convex-shaped iliac crest and a reduced posterior iliac spine on the hip An acetabular notch on the ischium The position of a small projection called the lesser trochanter close to the head of the femur

Prozostrodontia

5of7 · CC BY-SA 2.0 · 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
ProbainognathiaPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Amniota

Time the record covers

At most 32 million years on record.

Every occurrence read is dated to somewhere between 237 Mya and 205.7 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Middle Triassic — about 0 of 8 occurrencesLate Triassic — about 8 of 8 occurrencesLate Triassic238–237 Mya — about 0.2 occurrences237–235 Mya — about 0.4 occurrences235–234 Mya — about 0.4 occurrences234–233 Mya — about 0.4 occurrences233–232 Mya — about 0.5 occurrences232–231 Mya — about 0.5 occurrences231–230 Mya — about 0.5 occurrences230–229 Mya — about 0.5 occurrences229–228 Mya — about 0.5 occurrences228–227 Mya — about 0.4 occurrences227–226 Mya — about 0.2 occurrences226–225 Mya — about 0.2 occurrences225–224 Mya — about 0.2 occurrences224–222 Mya — about 0.2 occurrences222–221 Mya — about 0.2 occurrences221–220 Mya — about 0.2 occurrences220–219 Mya — about 0.2 occurrences219–218 Mya — about 0.2 occurrences218–217 Mya — about 0.2 occurrences217–216 Mya — about 0.2 occurrences216–215 Mya — about 0.2 occurrences215–214 Mya — about 0.2 occurrences214–213 Mya — about 0.2 occurrences213–212 Mya — about 0.2 occurrences212–210 Mya — about 0.2 occurrences210–209 Mya — about 0.2 occurrences209–208 Mya — about 0.2 occurrences208–207 Mya — about 0.2 occurrences207–206 Mya — about 0.2 occurrences206–205 Mya — about 0.1 occurrences237.6 Mya205.1 Mya

8 occurrences of Prozostrodontia on record, most of them in the Late Triassic. 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

8 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

4 formations

Santa Maria — 29.70°S, 53.79°WSanta Maria — 29.63°S, 53.45°WCandelária — 29.67°S, 53.23°WCaturrita — 29.68°S, 52.84°WSanto Domingo — 28.50°S, 68.75°W

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

Prozostrodontia and its relatives

Late Triassic

Where Prozostrodontia and its relatives were recorded in the Late Triassic.

Found in the same rock

29 taxa

The Paleobiology Database records 6 sites for Prozostrodontia, 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

8 references

Each of the 8 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 Prozostrodontia

Credit
5of7
Licence
CC BY-SA 2.0
Commercial use
the licence allows it

No 3D scan of Prozostrodontia was found in Sketchfab.

Smithsonian Open Access and MorphoSource were 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 itProbainognathia through timeFormations of the Late TriassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Liu and Olsen 2010