Emydopidae

Kammerer, Christian F. & Angielczyk, Kenneth D., 2009, A proposed higher taxonomy of anomodont therapsids, Zootaxa 2018, pp. 1-24 : 8

Emydopidae (van Hoepen, 1934) Cluver & King, 1983

Definition: All taxa more closely related to Emydops arctatus ( Owen, 1876) Broom, 1913 a, than Cistecephalus microrhinus Owen, 1876 .

Taxonomic comments: Cluver & King (1983) established the family-level taxa Emydopidae and Emydopinae to contain Emydops Broom, 1912 b, despite the fact that van Hoepen (1934) had already named this taxon as the subfamily Emydopsinae [sic]. Phylogenetic analyses of dicynodonts (e. g., Angielczyk 2007; Fröbisch 2007; Fröbisch & Reisz 2008) consistently recover Emydops as the sister-group to the other wellknown emydopoids ( Myosaurus , Kingoria , and cistecephalids), so we restrict the external specifier to Cistecephalus Owen, 1876 .

Revised diagnosis: Two autapomorphies of Emydopidae are present in the data set of Angielczyk (2007): (1) lateral anterior palatal ridges present; (2) upper postcanine teeth located near lateral margin of the maxilla. One autapomorphy of Emydopidae is present in the data set of Fröbisch (2007): (1) maxillary non-caniniform teeth located near lateral margin of the maxilla. The addition of Emydops oweni to the data set of Fröbisch & Reisz (2008) renders the status of that character uncertain, because it could not be scored using the available specimens of E. oweni . However, one emydopid autapomorphy does exist in the data set of Fröbisch & Reisz (2008): (1) squared-off profile of occiput in posterior view present. Recent diagnoses of Emydops itself can be found in Keyser (1993; called Emydoses therein), King & Rubidge (1993), Ray (2001), and Fröbisch & Reisz (2008), with additional information in Angielczyk et al. (2005). The jaw of Emydops is the single most distinctive part of its skeleton, and is characterized by a shovel-shaped symphysis, weak posterior dentary sulci, a small number of medially located postcanine teeth, and a large, triangular lateral dentary shelf.