| Mesochelydia Temporal range:
| |
|---|---|
| |
| Kayentachelys | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Pantestudines |
| Clade: | Testudinata |
| Clade: | Rhaptochelydia |
| Clade: | Mesochelydia Joyce, 2017 |
| Subgroupings | |
Mesochelydia (from Greek mesos "middle" and chelys "turtle") is a clade within Pantestudines, more inclusive than Perichelydia, but less than Testudinata. The clade is known from the Early Jurassic to the Present, and contains all Jurassic representatives of Testudinata aside from Australochelys.[1] The ancestral condition for Mesochelydia is thought to be aquatic, as opposed to terrestrial for Testudinata.[2] They are distinguished from more basal testudinatans by the presence of the following characters: strap like pectoral girdle, supramarginals absent, reduced posterior entoplastral process, eleven pairs of peripherals, elongate processus interfenestralis, paired basioccipital tubercles, fully formed cavum tympani and antrum postoticum, single vomer, confluent external nares, lacrimals and supratemporals absent.[1]
- ^ a b Joyce, Walter G. (April 2017). "A Review of the Fossil Record of Basal Mesozoic Turtles". Bulletin of the Peabody Museum of Natural History. 58 (1): 65–113. doi:10.3374/014.058.0105. ISSN 0079-032X. S2CID 54982901.
- ^ Sterli, Juliana; de la Fuente, Marcelo S.; Rougier, Guillermo W. (2018-07-04). "New remains of Condorchelys antiqua (Testudinata) from the Early-Middle Jurassic of Patagonia: anatomy, phylogeny, and paedomorphosis in the early evolution of turtles". Journal of Vertebrate Paleontology. 38 (4): (1)–(17). doi:10.1080/02724634.2018.1480112. hdl:11336/99525. ISSN 0272-4634. S2CID 109556104.