Dermochelyoidae

Belongs within: Centrocryptodira.

The clade Dermochelyoidae unites the living leatherback turtle Dermochelys coriacea and its close fossil relatives with the extinct family Protostegidae. Dermochelys coriacea is the largest living turtle and is readily distinguished from other living Testudines by the lack of a solid external shell.

Synapomorphies (from Gaffney & Meylan 1988): Jugal very large, ventral process extending posteriorly to form most of cheek margin; basisphenoid and occipital elements usually poorly ossified, with portions remaining cartilaginous; forelimbs very long in relation to hindlimbs and body; trochanter major of femur very long in relation to trochanter minor, projecting proximal to femur head; intertrochanteric fossa largely obliterated by fusion of trochanter bases.

<==Dermochelyoidae [Dermochelyoidea]
    |--ProtostegidaeGM88
    |    |  i. s.: Pneumatoarthrus peloreus Cope 1870B93
    |    |--ChelospharginaeGM88
    |    |    |--ChelosphargisGM88
    |    |    `--Calcarichelys Zengerl 1953GM88, D07
    |    |         `--C. gemmaD07
    |    `--ProtosteginaeGM88
    |         |--Archelon Wieland 1896GM88, D07
    |         |    `--A. ischyrosD07
    |         `--ProtostegaB93
    |              |--P. eaglefordensis Zangerl 1953B93
    |              `--P. gigas Cope 1871JPG04
    `--DermochelyidaeGM88
         |--Eosphargis gigas (Owen 1861)GM88, B93
         `--+--Dermochelys Blainville 1816GM88, JPG04 [incl. Sphargis Merrem 1820JPG04]
            |    `--D. coriacea (Vandelli 1761)C18 [=Testudo coriaceusJPG04]
            `--PsephophorusGM88
                 |--P. calvertensis Palmer 1909K95
                 |--P. eocaenus Andrews 1901K95
                 |--P. oregonensis Palmer 1940K95
                 |--P. polygonus v. Meyer 1847K95
                 |--P. pseudostracion (Gervais 1849)K95
                 |--P. rupeliensis (v. Beneden 1883)K95
                 |--P. scaldii (van Beneden 1871)K95
                 `--P. terrypratchetti Köhler 1995K95

*Type species of generic name indicated

References

[B93] Benton, M. J. 1993. Reptilia. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 681–715. Chapman & Hall: London.

[C18] Cogger, H. G. 2018. Reptiles and Amphibians of Australia updated 7^th ed. CSIRO Publishing: Collingwood.

[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.

[GM88] Gaffney, E. S., & P. A. Meylan. 1988. A phylogeny of turtles. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 1. Amphibians, Reptiles, Birds pp. 157–219. Clarendon Press: Oxford.

[JPG04] Joyce, W. G., J. F. Parham & J. A. Gauthier. 2004. Developing a protocol for the conversion of rank-based taxon names to phylogenetically defined clade names, as exemplified by turtles. Journal of Paleontology 78 (5): 989–1013.

[K95] Köhler, R. 1995. A new species of the fossil turtle Psephophorus (order Testudines) from the Eocene of the South Island, New Zealand. Journal of the Royal Society of New Zealand 25: 371–384.