Akidnognathidae

Huttenlocker, Adam, 2009, An investigation into the cladistic relationships and monophyly of therocephalian therapsids (Amniota: Synapsida), Zoological Journal of the Linnean Society 157 (4), pp. 865-891 : 889

Akidnognathidae (eight characters)

2. Septomaxilla is enlarged and well exposed outside of the external naris, broadly overlapping the premaxilla anteriorly (1).

3. External nares are enlarged, close-set and face anteriorly (1).

21. Median fronto-nasal crest present (1). (Absent in Euchambersia ; conv. in Theriognathus .)

36. A separate palatal housing for the lower canine is created by an extension of the premaxilla and maxilla (2).

39. Anterior-most portion of the vomer broadly overlaps the ventral surface of the premaxilla (1).

77. Incisors relatively spatulate, concave lingually with mesiolingual and distolingual crests (1). (From Hopson & Barghusen, 1986; conv. in cynodonts.)

81. Upper postcanines in adults few, five or less (1) or completely absent (2). (Modified from Kemp, 1972b; van den Heever, 1994; conv. in lycosuchids and Theriognathus , which also appear to have reduced the postcanine dentition.)

88. Parietal crest extends forward in adults to include the parietal foramen (1). (From Hopson & Kitching, 2001; conv in cynodonts, Ictidosuchops and Ictidosuchoides .)