Stylemys

Stylemys is the first fossil genus of dry land tortoise belonging to the order Testudines discovered in the United States. The genus lived in temperate to subtropical areas of North America, Europe, and Asia, based on fossil distribution. The genus was first described in 1851 by Joseph Leidy. The tortoise was common in the prehistoric Badlands, especially Nebraska and South Dakota. The species has also been found in the formations in and around Badlands National Park. Fossil fragments have also been found in the Palm Park Formation of New Mexico.

Stylemys

Ryan Somma · CC BY 2.0 · 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
TestudininaePBDB
Diet
herbivore, herbivorePBDB, for Testudinidae
Life habit
ground dwellingPBDB, for Testudinidae
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Testudinidae

Time the record covers

At least 21 million years on record.

The record covers at least 33.9 Mya to 12.5 Mya. No occurrence read is dated outside 41.03 Mya to 5.333 Mya.

Eocene — about 9 of 38 occurrencesEoceneOligocene — about 20 of 38 occurrencesOligoceneMiocene — about 9 of 38 occurrencesMiocenePliocene — about 0 of 38 occurrences42–41 Mya — about 0.0 occurrences41–39 Mya — about 0.1 occurrences39–38 Mya — about 0.1 occurrences38–37 Mya — about 0.7 occurrences37–36 Mya — about 4 occurrences36–34 Mya — about 4 occurrences34–33 Mya — about 6 occurrences33–32 Mya — about 7 occurrences32–31 Mya — about 2 occurrences31–29 Mya — about 1 occurrence29–28 Mya — about 2 occurrences28–27 Mya — about 1 occurrence27–26 Mya — about 0.8 occurrences26–24 Mya — about 0.8 occurrences24–23 Mya — about 0.8 occurrences23–22 Mya — about 0.9 occurrences22–21 Mya — about 0.9 occurrences21–19 Mya — about 0.9 occurrences19–18 Mya — about 0.9 occurrences18–17 Mya — about 0.8 occurrences17–16 Mya — about 0.6 occurrences16–15 Mya — about 0.2 occurrences15–13 Mya — about 0.2 occurrences13–12 Mya — about 0.5 occurrences12–11 Mya — about 1 occurrence11–9.6 Mya — about 1 occurrence9.6–8.3 Mya — about 0.2 occurrences8.3–7.1 Mya — about 0.1 occurrences7.1–5.9 Mya — about 0.1 occurrences5.9–4.6 Mya — about 0.0 occurrences33.9 Mya12.5 Mya41.7 Mya4.6 Mya

38 occurrences of Stylemys 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

38 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

9 formations

Brule — 42.86°N, 103.57°WBrule — 43.90°N, 102.40°WBrule — 43.30°N, 102.50°WBrule — 43.75°N, 102.50°WChadron — 42.86°N, 103.57°WChadron — 42.80°N, 103.40°WChadron — 42.40°N, 103.80°WJohn Day — 44.41°N, 118.88°WJohn Day — 44.70°N, 119.63°WWhite River — 40.80°N, 103.10°WSespe — 34.25°N, 118.96°WYolomécatl — 17.46°N, 97.58°WCypress HIlls — 49.57°N, 109.88°WLoup Fork — 42.70°N, 102.50°WRosebud — 43.18°N, 102.30°W

Loading coastlines…

The named rock units Stylemys has been recovered from, largest first. Drawn where the rock is now, not where it formed. 9 occurrences have no formation on record, which is common for older literature.

Stylemys and its relatives

Oligocene

Where Stylemys and its relatives were recorded in the Oligocene.

Found in the same rock

264 taxa

The Paleobiology Database records 31 sites for Stylemys, 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

23 references

Each of the 38 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. 11 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 content4

Picture of Stylemys

Credit
Ryan Somma
Licence
CC BY 2.0
Commercial use
the licence allows it

3D scan

Licence
CC0 — this site’s default, not the record’s
Commercial use
the licence allows it
Specimen
Stylemys nebrascensis Leidy, 1851

Structured light scan

Licence
not stated by the source
Commercial use
cannot be read from the licence given — check the record
Specimen
Stylemys nebrascensis · dmnh:701

3D model

Source
Sketchfab
Licence
CC Attribution-NonCommercial
Commercial use
the licence does not allow it

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 itTestudininae through timeFormations of the OligoceneThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Leidy 1851