Plastomeninae is an extinct subfamily of softshell turtles that inhabited most of North America from the Cretaceous to the Eocene. Members of this subfamily are also known as plastomenines.

Plastomeninae
Temporal range: Campanian– Lutetian
Plastomenus sp.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Family: Trionychidae
Subfamily: Plastomeninae
Hay, 1902
Genera

See text

Taxonomy and evolution edit

They are thought to have originated in North America during or shortly before the Campanian from basal trionychids that dispersed from Asia. They reached their peak diversity from the Maastrichtian through the Paleocene, having survived the Cretaceous–Paleogene extinction event. However, they went entirely extinct by the Lutetian. The last surviving member of this subfamily is thought to have been Plastomenus thomasii, which is the only known member of the subfamily to have survived past the Paleocene into the Eocene.[1]

Morphological analysis supports them being the sister taxon to the flapshell turtles (subfamily Cyclanorbinae), which still survive to the present day in parts of tropical Asia and Africa, in contrast to the exclusively North American plastomenines.[1][2][3]

Genera edit

These extinct genera are known:[1][4]

References edit

  1. ^ a b c Jasinski, Steven E.; Heckert, Andrew B.; Sailar, Ciara; Lichtig, Asher J.; Lucas, Spencer G.; Dodson, Peter (2022-07-01). "A softshell turtle (Testudines: Trionychidae: Plastomeninae) from the uppermost Cretaceous (Maastrichtian) Hell Creek Formation, North Dakota, USA, with implications for the evolutionary relationships of plastomenines and other trionychids". Cretaceous Research. 135: 105172. doi:10.1016/j.cretres.2022.105172. ISSN 0195-6671. S2CID 246803273.
  2. ^ Hutchison, J. Howard (2009-11-05). "New soft-shelled turtles (Plastomeninae, Trionychidae, Testudines) from the Late Cretaceous and Paleocene of North America". PaleoBios. 29 (2). doi:10.5070/P9292021801. ISSN 0031-0298.
  3. ^ Walter G. Joyce; Ariel Revan; Tyler R. Lyson; Igor G. Danilov (2009). "Two New Plastomenine Softshell Turtles from the Paleocene of Montana and Wyoming" (PDF). Bulletin of the Peabody Museum of Natural History. 50 (2): 307–325. doi:10.3374/014.050.0202. S2CID 85505337.
  4. ^ "Fossilworks: Plastomenidae". www.fossilworks.org. Retrieved 2022-03-28.