Exostinus

Exostinus is an extinct genus of xenosaurid lizard from the Late Cretaceous to Oligocene of the western United States. It was named in 1873 by Edward Drinker Cope as Exostinus serratus for jaw and skull bones found in the White River Formation of Colorado showing distinguishing cranial scutes. Material of E. serratus is also known from the Brule Formation, also Middle Oligocene in age, but in Wyoming. A second species, E. lancensis was named in 1928 by Charles W. Gilmore and is also known from skull and jaw bones, from the Maastrichtian Hell Creek, Lance and Fort Union Formations, and the Paleocene Tongue River Formation. Other species named by Gilmore are now considered synonyms of E. lancensis.

Exostinus

J. Hatcher · CC0 · via GBIF. 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
XenosauridaePBDB
Diet
carnivorePBDB, for Xenosauridae
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Xenosauridae

Time the record covers

At least 38 million years on record.

The record covers at least 72.2 Mya to 33.9 Mya. No occurrence read is dated outside 83.6 Mya to 31.8 Mya.

Late Cretaceous — about 21 of 27 occurrencesLate CretaceousPaleocene — about 3 of 27 occurrencesPaleoceneEocene — about 2 of 27 occurrencesEoceneOligocene — about 1 of 27 occurrences85–83 Mya — about 0.3 occurrences83–81 Mya — about 0.6 occurrences81–79 Mya — about 0.6 occurrences79–77 Mya — about 0.6 occurrences77–76 Mya — about 0.6 occurrences76–74 Mya — about 0.6 occurrences74–72 Mya — about 1.0 occurrences72–70 Mya — about 5 occurrences70–68 Mya — about 5 occurrences68–67 Mya — about 5 occurrences67–65 Mya — about 2 occurrences65–63 Mya — about 0.8 occurrences63–61 Mya — about 1 occurrence61–59 Mya — about 0.3 occurrences58–56 Mya — about 0.0 occurrences56–54 Mya — about 0.4 occurrences54–52 Mya — about 0.4 occurrences52–51 Mya — about 0.4 occurrences51–49 Mya — about 0.3 occurrences49–47 Mya — about 0.3 occurrences47–45 Mya — about 0.2 occurrences34–33 Mya — about 0.6 occurrences33–31 Mya — about 0.4 occurrences72.2 Mya33.9 Mya85 Mya31 Mya

27 occurrences of Exostinus on record, most of them in the Late Cretaceous. 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

27 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

Lance — 43.12°N, 104.64°WLance — 41.57°N, 108.67°WLance — 43.15°N, 104.57°WLance — 43.13°N, 104.49°WLance — 43.24°N, 104.29°WLance — 43.18°N, 104.51°WHell Creek — 47.80°N, 106.10°WHell Creek — 47.55°N, 107.13°WHell Creek — 47.52°N, 106.40°WHell Creek — 47.55°N, 107.25°WHell Creek — 45.50°N, 103.10°WFort Union — 41.30°N, 107.74°WFort Union — 46.05°N, 104.48°WFort Union — 47.60°N, 107.00°WKaiparowits — 37.80°N, 111.50°WKaiparowits — 37.42°N, 111.77°WTakli — 21.15°N, 79.10°EJudith River — 47.81°N, 109.59°WBrule — 40.74°N, 103.19°WEl Gallo — 30.05°N, 115.76°WBridger — 41.50°N, 110.60°WWind River — 43.20°N, 107.10°W

Loading coastlines…

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

Exostinus and its relatives

Late Cretaceous

Where Exostinus and its relatives were recorded in the Late Cretaceous.

Found in the same rock

535 taxa

The Paleobiology Database records 23 sites for Exostinus, 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

16 references

Each of the 27 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. 4 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 Exostinus

Source
GBIF
Credit
J. Hatcher
Licence
CC0
Commercial use
the licence allows it

No 3D scan of Exostinus was found in MorphoSource and Sketchfab.

Smithsonian Open Access was 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 itXenosauridae through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Cope 1873