Vancleavea

Vancleavea is a genus of extinct, armoured, non-archosaurian archosauriforms from the Late Triassic of western North America. The type and only known species is V. campi, named by Robert Long & Phillip A Murry in 1995. At that time, the genus was only known from fragmentary bones including osteoderms and vertebrae. However, since then many more fossils have been found, including a pair of nearly complete skeletons discovered in 2002. These finds have shown that members of the genus were bizarre semiaquatic reptiles. Vancleavea individuals had short snouts with large, fang-like teeth, and long bodies with small limbs. They were completely covered with bony plates known as osteoderms, which came in several different varieties distributed around the body. Phylogenetic analyses by professional paleontologists have shown that Vancleavea was an archosauriform, part of the lineage of reptiles that would lead to archosaurs such as dinosaurs and crocodilians. Vancleavea lacks certain traits which are present in most other archosauriforms, most notably the antorbital, mandibular and supratemporal fenestrae, which are weight-saving holes in the skulls of other taxa. However, other features clearly support its archosauriform identity, including a lack of intercentra, the presence of osteoderms, an ossified laterosphenoid, and several adaptations of the femur and ankle bones. In 2016, a new genus of archosauriform, Litorosuchus, was described. This genus resembled both Vancleavea and more typical archosauriforms in different respects, allowing Litorosuchus to act as a transitional fossil linking Vancleavea to less aberrant archosauriforms.

Vancleavea

Neil Pezzoni · CC BY 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
DoswelliidaePBDB
Diet
carnivorePBDB
Life habit
aquaticPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
freshwaterPBDB

Time the record covers

At least 21 million years on record.

The record covers at least 227.3 Mya to 205.7 Mya. No occurrence read is dated outside 237 Mya to 201.4 Mya.

Middle Triassic — about 0 of 25 occurrencesLate Triassic — about 25 of 25 occurrencesLate TriassicEarly Jurassic — about 0 of 25 occurrences238–236 Mya — about 0.1 occurrences236–235 Mya — about 0.2 occurrences235–234 Mya — about 0.2 occurrences234–233 Mya — about 0.2 occurrences233–232 Mya — about 0.2 occurrences232–230 Mya — about 0.2 occurrences230–229 Mya — about 0.2 occurrences229–228 Mya — about 0.2 occurrences228–227 Mya — about 0.8 occurrences227–225 Mya — about 1 occurrence225–224 Mya — about 1 occurrence224–223 Mya — about 1 occurrence223–222 Mya — about 1 occurrence222–220 Mya — about 1 occurrence220–219 Mya — about 1 occurrence219–218 Mya — about 1 occurrence218–217 Mya — about 1 occurrence217–215 Mya — about 1 occurrence215–214 Mya — about 1 occurrence214–213 Mya — about 1 occurrence213–212 Mya — about 1 occurrence212–211 Mya — about 1 occurrence211–209 Mya — about 1 occurrence209–208 Mya — about 1 occurrence208–207 Mya — about 1 occurrence207–206 Mya — about 1 occurrence206–204 Mya — about 0.6 occurrences204–203 Mya — about 0.6 occurrences203–202 Mya — about 0.6 occurrences202–201 Mya — about 0.3 occurrences227.3 Mya205.7 Mya237.7 Mya200.7 Mya

25 occurrences of Vancleavea 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

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

5 formations

Chinle — 36.33°N, 106.47°WChinle — 35.11°N, 109.83°WChinle — 34.44°N, 109.46°WChinle — 37.56°N, 110.28°WChinle — 34.95°N, 109.76°WChinle — 35.82°N, 111.25°WChinle — 35.03°N, 109.83°WChinle — 34.83°N, 109.83°WChinle — 34.68°N, 109.58°WTecovas — 33.42°N, 101.15°WTecovas — 35.38°N, 102.16°WRedonda — 34.94°N, 103.43°WRedonda — 35.00°N, 103.67°WSanta Rosa — 35.48°N, 105.88°WPetrified Forest — 36.21°N, 106.62°W

Loading coastlines…

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

Vancleavea and its relatives

Late Triassic

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

Found in the same rock

151 taxa

The Paleobiology Database records 25 sites for Vancleavea, 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

9 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. 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 content2

Picture of Vancleavea

Credit
Neil Pezzoni
Licence
CC BY 4.0
Commercial use
the licence allows it

CT scan

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
Vancleavea campi · pefo:56059

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 itDoswelliidae through timeFormations of the Late TriassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Long and Murry 1995