Millerosaurus

Millerosaurus is an extinct genus of millerettid reptiles from the Late Permian of South Africa. Jenkins et al. (2025) recognized both species of Millerosaurus as juvenile individuals of Milleretta, since the observed anatomical differences can be explained by changes seen through ontogeny in the latter. Under this reinterpretation, Millerosaurus would be a junior synonym of Milleretta.

Millerosaurus

Conty · CC BY 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
MillerettidaePBDB

Time the record covers

At most 8 million years on record.

Every occurrence read is dated to somewhere between 259.857 Mya and 251.902 Mya, and nothing in the dating separates them, so that window is what the record shows rather than a span.

Permian — about 4 of 4 occurrencesPermianEarly Triassic — about 0 of 4 occurrences260–260 Mya — about 0.0 occurrences260–259 Mya — about 0.1 occurrences259–259 Mya — about 0.1 occurrences259–259 Mya — about 0.1 occurrences259–259 Mya — about 0.1 occurrences259–258 Mya — about 0.1 occurrences258–258 Mya — about 0.1 occurrences258–258 Mya — about 0.1 occurrences258–257 Mya — about 0.1 occurrences257–257 Mya — about 0.1 occurrences257–257 Mya — about 0.1 occurrences257–256 Mya — about 0.1 occurrences256–256 Mya — about 0.1 occurrences256–256 Mya — about 0.1 occurrences256–256 Mya — about 0.1 occurrences256–255 Mya — about 0.1 occurrences255–255 Mya — about 0.1 occurrences255–255 Mya — about 0.1 occurrences255–254 Mya — about 0.1 occurrences254–254 Mya — about 0.1 occurrences254–254 Mya — about 0.1 occurrences254–253 Mya — about 0.1 occurrences253–253 Mya — about 0.1 occurrences253–253 Mya — about 0.1 occurrences253–253 Mya — about 0.1 occurrences253–252 Mya — about 0.1 occurrences252–252 Mya — about 0.1 occurrences252–252 Mya — about 0.0 occurrences260.4 Mya251.4 Mya

4 occurrences of Millerosaurus 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

4 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

1 formation

  • Balfour Formation · Beaufort GroupEastern Cape, Western Cape · ZA · 259.857–251.902 Mya4
Balfour — 31.87°S, 24.55°EBalfour — 31.95°S, 23.77°EBalfour — 32.06°S, 24.19°E

Loading coastlines…

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

Millerosaurus and its relatives

Permian

Where Millerosaurus and its relatives were recorded in the Permian.

Found in the same rock

The Paleobiology Database records no fossil sites for Millerosaurus, so there is nothing to compare it with.

Entered from

2 references

Each of the 4 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 Millerosaurus

Credit
Conty
Licence
CC BY 3.0
Commercial use
the licence allows it

No 3D scan of Millerosaurus 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 itMillerettidae through timeFormations of the PermianThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Broom 1948