Compsemys

Compsemys is an extinct genus of compsemyid turtle that lived in North America and possibly Europe during the Late Cretaceous and Paleocene. The type species, C. victa, was first described by Joseph Leidy from the Hell Creek Formation in Montana in 1856, but Jasinski et al. (2026) suggested most of the specimens referred to C. victa actually represent indeterminate species of this genus. Meanwhile, C. puercensis and C. torrejonensis, both from the Paleocene Nacimiento Formation of New Mexico, are valid species. Another potential species, C. russelli, was described in 2012 from Paleocene deposits in France., but Jasinski et el. (2026) suggested Berruchelus represents a distinct genus from Compsemys.

Compsemys

B Louque · 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
ParacryptodiraPBDB
Motility
actively mobilePBDB, for Osteichthyes
Environment
terrestrialPBDB, for Diapsida

Time the record covers

At least 26 million years on record.

The record covers at least 83.6 Mya to 57.5 Mya. No occurrence read is dated outside 85.7 Mya to 56 Mya.

Late Cretaceous — about 127 of 167 occurrencesLate CretaceousPaleocene — about 40 of 167 occurrencesPaleoceneEocene — about 0 of 167 occurrences86–85 Mya — about 0.4 occurrences85–84 Mya — about 1.0 occurrences84–83 Mya — about 2 occurrences83–82 Mya — about 3 occurrences82–81 Mya — about 3 occurrences81–80 Mya — about 3 occurrences80–79 Mya — about 3 occurrences79–78 Mya — about 3 occurrences78–77 Mya — about 3 occurrences77–76 Mya — about 3 occurrences76–75 Mya — about 3 occurrences75–74 Mya — about 3 occurrences74–73 Mya — about 3 occurrences73–72 Mya — about 7 occurrences72–71 Mya — about 15 occurrences71–70 Mya — about 15 occurrences70–69 Mya — about 15 occurrences69–68 Mya — about 15 occurrences68–67 Mya — about 15 occurrences67–66 Mya — about 15 occurrences66–65 Mya — about 12 occurrences65–64 Mya — about 12 occurrences64–63 Mya — about 5 occurrences63–62 Mya — about 3 occurrences62–61 Mya — about 2 occurrences61–60 Mya — about 0.4 occurrences60–58 Mya — about 0.4 occurrences58–57 Mya — about 0.4 occurrences57–56 Mya — about 0.8 occurrences56–55 Mya — about 0.3 occurrences83.6 Mya57.5 Mya86.3 Mya55.4 Mya

167 occurrences of Compsemys 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

167 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

22 formations

Hell Creek — 47.80°N, 106.10°WHell Creek — 46.03°N, 103.77°WHell Creek — 46.21°N, 103.77°WHell Creek — 46.38°N, 103.96°WHell Creek — 45.95°N, 103.96°WHell Creek — 46.41°N, 103.94°WHell Creek — 46.10°N, 103.30°WHell Creek — 46.46°N, 104.02°WHell Creek — 46.33°N, 103.90°WHell Creek — 45.94°N, 103.95°WHell Creek — 45.53°N, 101.63°WHell Creek — 47.88°N, 106.20°WHell Creek — 47.55°N, 107.13°WHell Creek — 47.62°N, 107.32°WHell Creek — 47.52°N, 106.98°WHell Creek — 47.57°N, 107.10°WHell Creek — 47.52°N, 106.40°WHell Creek — 47.55°N, 107.25°WHell Creek — 47.60°N, 106.43°WHell Creek — 47.52°N, 107.18°WHell Creek — 47.60°N, 106.27°WHell Creek — 47.60°N, 107.23°WHell Creek — 46.90°N, 101.50°WHell Creek — 47.60°N, 107.00°WHell Creek — 46.70°N, 100.25°WHell Creek — 46.41°N, 103.50°WHell Creek — 45.89°N, 104.55°WHell Creek — 45.87°N, 103.79°WDenver — 39.70°N, 104.70°WDenver — 39.75°N, 105.22°WDenver — 38.80°N, 104.80°WDenver — 38.86°N, 104.61°WDenver — 39.30°N, 104.30°WDenver — 39.63°N, 104.33°WDenver — 39.50°N, 104.70°WDenver — 38.91°N, 104.53°WLance — 43.30°N, 104.37°WLance — 43.12°N, 104.64°WLance — 41.57°N, 108.67°WLance — 43.18°N, 104.53°WLance — 43.15°N, 104.57°WLance — 43.13°N, 104.49°WLance — 43.25°N, 104.52°WLance — 45.39°N, 103.70°WLance — 45.60°N, 103.63°WKaiparowits — 37.58°N, 111.94°WKaiparowits — 37.75°N, 111.61°WKaiparowits — 37.62°N, 111.80°WKaiparowits — 37.46°N, 111.34°WKaiparowits — 37.30°N, 112.43°WKaiparowits — 37.82°N, 111.40°WNorth Horn — 39.10°N, 111.80°WNorth Horn — 39.18°N, 111.27°WNorth Horn — 39.00°N, 111.00°WFerris — 41.80°N, 107.00°WFerris — 41.94°N, 106.88°WFerris — 41.95°N, 106.89°WNacimiento — 36.20°N, 107.78°WNacimiento — 36.23°N, 107.71°WNacimiento — 36.73°N, 108.22°WNacimiento — 36.07°N, 107.97°WKirtland — 36.34°N, 108.08°WKirtland — 36.20°N, 108.10°WKirtland — 36.34°N, 108.21°WKirtland — 36.51°N, 108.32°WCerro del Pueblo — 26.12°N, 101.12°WCerro del Pueblo — 25.47°N, 101.42°WCerro del Pueblo — 25.50°N, 101.75°WLaramie — 40.39°N, 104.49°WLaramie — 40.95°N, 104.92°WLaramie — 39.73°N, 105.05°WLaramie — 39.50°N, 104.70°WFruitland — 36.49°N, 108.49°WFruitland — 36.12°N, 107.78°WFort Union — 43.85°N, 108.35°WFort Union — 46.05°N, 104.48°WFort Union — 39.20°N, 108.20°WFort Union — 47.60°N, 107.00°WKirtland? — 36.29°N, 108.54°WKirtland? — 36.27°N, 108.17°WOjo Alamo — 36.32°N, 108.03°WOjo Alamo — 36.34°N, 108.10°WWahweap — 37.59°N, 112.90°WWahweap — 37.63°N, 112.12°WMilk River — 49.08°N, 111.44°WTullock — 47.80°N, 106.10°WFrenchman — 49.00°N, 110.55°WOhio Creek — 40.28°N, 108.30°WEl Gallo — 30.06°N, 115.78°WTwo Medicine — 48.49°N, 112.47°WAguja — 28.94°N, 103.37°W

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The named rock units Compsemys 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.

Compsemys and its relatives

Late Cretaceous

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

Found in the same rock

593 taxa

The Paleobiology Database records 156 sites for Compsemys, 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

43 references

Each of the 167 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. 31 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 content2

Picture of Compsemys

Source
GBIF
Credit
B Louque
Licence
CC0
Commercial use
the licence allows it

Photogrammetry

Licence
In Copyright
Commercial use
cannot be read from the licence given — check the record
Specimen
Compsemys victa · UCM:Paleontology:UCM:FossilVert:49223

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

Everything alive alongside itParacryptodira through timeFormations of the Late CretaceousThe world it lived on

Occurrence data from the Paleobiology Database, CC BY 4.0. Leidy 1856