Ultrastenos willisi
Ultrastenos is an extinct genus of Australian mekosuchine crocodilian that lived during the Late Oligocene in northwestern Queensland, Australia. Following its discovery, it was speculated that Ultrastenos was a slender-snouted animal similar to modern gharials or freshwater crocodiles due to the seemingly abruptly narrowing mandible. However, a later study found that this was a misinterpretation of the fossil specimen and that Ultrastenos instead had a more generalized lower jaw. The same publication also provided evidence that the fossils of Ultrastenos belonged to the same animal previously named "Baru" huberi, adding further evidence to the idea that the animal was short snouted, contrary to the initial hypothesis. Given that "Baru" huberi was named first, the type species of Ultrastenos changed from U. willisi to U. huberi in accordance with the rules of the ICZN. Ultrastenos was a small mekosuchine, measuring upwards of 1.5 m long.

Uncredited · 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
- UltrastenosPBDB
- Diet
- carnivorePBDB, for Crocodylia
- Motility
- actively mobilePBDB, for Osteichthyes
- Environment
- marinePBDB, for Mesoeucrocodylia
Time the record covers
At most 4.3 million years on record.
The one occurrence read is dated to somewhere between 27.3 Mya and 23.04 Mya, which is a dating window rather than a span.
1 occurrence of Ultrastenos willisi on record, most of them in the Oligocene. 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
1 occurrences- Oligocene100%
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
Loading coastlines…
The named rock units Ultrastenos willisi has been recovered from, largest first. Drawn where the rock is now, not where it formed.
Ultrastenos willisi and its relatives
OligoceneWhere Ultrastenos willisi and its relatives were recorded in the Oligocene.
Found in the same rock
2 taxa- Baru wickeni1 site
- Morelia riversleighensis1 site
The Paleobiology Database records 1 site for Ultrastenos willisi, and this reads all of them. The number is how many of those sites it was catalogued from too.
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
1 referenceEach of the 1 occurrence 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 Ultrastenos willisi
- Source
- Wikipedia/Commons
- Credit
- nobody named on the record
- Licence
- not stated by the source
- Commercial use
- cannot be read from the licence given — check the record
No 3D scan of Ultrastenos willisi 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
- Source
- Wikipedia, “Ultrastenos”
- 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 itUltrastenos through timeFormations of the OligoceneThe world it lived on
Occurrence data from the Paleobiology Database, CC BY 4.0. Stein et al. 2016