Opisthias

Opisthias is a genus of sphenodont reptile. The type species, Opisthias rarus, is known from the Late Jurassic (Kimmeridgian-Tithonian) of western North America.

Opisthias

Uncredited · CC BY-SA 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
SphenodontiaPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Amniota

Time the record covers

At least 43 million years on record.

The record covers at least 184.2 Mya to 141 Mya. No occurrence read is dated outside 192.9 Mya to 132.6 Mya.

Early Jurassic — about 6 of 29 occurrencesEarly JurassicMiddle Jurassic — about 0 of 29 occurrencesLate Jurassic — about 20 of 29 occurrencesLate JurassicEarly Cretaceous — about 3 of 29 occurrencesEarly Cretaceous194–192 Mya — about 0.6 occurrences192–190 Mya — about 1 occurrence190–188 Mya — about 1 occurrence188–186 Mya — about 1 occurrence186–184 Mya — about 1 occurrence156–154 Mya — about 0.4 occurrences154–152 Mya — about 2 occurrences152–150 Mya — about 2 occurrences150–148 Mya — about 4 occurrences148–146 Mya — about 6 occurrences146–144 Mya — about 5 occurrences144–142 Mya — about 2 occurrences142–140 Mya — about 1 occurrence140–138 Mya — about 0.8 occurrences138–136 Mya — about 0.2 occurrences136–133 Mya — about 0.1 occurrences133–131 Mya — about 0.1 occurrences184.2 Mya141 Mya194 Mya131 Mya

29 occurrences of Opisthias on record, most of them in the Late Jurassic. 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

29 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

Morrison — 40.42°N, 109.21°WMorrison — 41.89°N, 106.00°WMorrison — 39.24°N, 109.00°WMorrison — 38.54°N, 105.19°WMorrison — 39.17°N, 108.77°WMorrison — 40.44°N, 109.30°WMorrison — 41.88°N, 106.11°WMorrison — 40.50°N, 109.17°WMorrison — 39.15°N, 108.77°WMorrison — 44.46°N, 104.73°WMorrison — 39.01°N, 111.02°WMorrison — 40.30°N, 108.57°WLa Boca — 26.60°N, 99.52°WKirkwood — 33.46°S, 25.52°ELulworth — 50.60°N, 1.97°W

Loading coastlines…

The named rock units Opisthias has been recovered from, largest first. Drawn where the rock is now, not where it formed. 1 occurrence has no formation on record, which is common for older literature.

Opisthias and its relatives

Late Jurassic

Where Opisthias and its relatives were recorded in the Late Jurassic.

Found in the same rock

286 taxa

The Paleobiology Database records 28 sites for Opisthias, 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 29 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 Opisthias

Credit
nobody named on the record
Licence
CC BY-SA 4.0
Commercial use
the licence allows it

No 3D scan was found. Smithsonian Open Access, MorphoSource and Sketchfab were all searched.

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 itSphenodontia through timeFormations of the Late JurassicThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Gilmore 1909