Trionyx ellipticus Hay 1908 (softshell turtle)

Reptilia - Testudines - Trionychidae

Alternative combinations: Aspideretes ellipticus, Hummelichelys ellipticus

Synonyms: Aspideretes annae Zangerl 1944, Aspideretes grangeri Hay 1908, Hummelichelys annae Zangerl 1944, Hummelichelys grangeri Hay 1908

Full reference: O. P. Hay. 1908. The fossil turtles of North America. Carnegie Institution of Washington Publication 75:1-568

Belongs to Trionyx according to N. S. Vitek and W. G. Joyce 2015

See also Chkhikvadze 2000, Hay 1908 and Zangerl 1944

Sister taxa: Trionyx admirabilis, Trionyx aequa, Trionyx allani, Trionyx austerus, Trionyx baynshirensis, Trionyx beecheri, Trionyx boulengeri, Trionyx capellinii, Trionyx dissolutus, Trionyx eloisae, Trionyx foveatus, Trionyx gangeticus, Trionyx gilbentuensis, Trionyx gobiensis, Trionyx gregarius, Trionyx henrici, Trionyx ikoviensis, Trionyx impressus, Trionyx jixiensis, Trionyx johnsoni, Trionyx kansaiensis, Trionyx latus, Trionyx leucopotamicus, Trionyx linchuensis, Trionyx messelianus, Trionyx miensis, Trionyx minusculus, Trionyx miocaenus, Trionyx mira, Trionyx ninae, Trionyx onomatoplokos, Trionyx phayrei, Trionyx pliocenicus, Trionyx reesidei, Trionyx riabinini, Trionyx robustus, Trionyx shiluutulensis, Trionyx silvestris, Trionyx singularis, Trionyx triunguis, Trionyx uintaensis, Trionyx vegetus, Trionyx vindobonensis

Type specimens:

  • Trionyx ellipticus: AMNH 1117, a carapace
  • Aspideretes annae: FMNH P 27241 (formerly UND 663), a partial skeleton (nearly complete carapace and plastron, isolated extremity bones). Its type locality is East of Little America, which is in a Bridgerian mire/swamp claystone in the Bridger Formation of Wyoming.
  • Aspideretes grangeri: AMNH 3942, a partial shell (carapace). Its type locality is Cottonwood Creek, about half a mile below the Henry's Fork stage road (B3), which is in a Bridgerian terrestrial horizon in Wyoming.

Ecology: aquatic piscivore-carnivore

Distribution: found only at Grizzly Buttes (Eocene of Wyoming)

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Specimen images are retrieved through the ePANDDA API.


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