Laccosaurus watsoni, HAUGHTON, 1925

LACCOSAURUS WATSONI HAUGHTON, 1925

Laccosaurus watsoni Haughton, 1925: 236 , original description. Damiani & Rubidge (2003: 29).

Uranocentrodon senekalensis Romer (1947: 200)

Uranocentrodon watsoni ( Haughton, 1925) – Ochev (1966: 157), nov. comb.

Uranocentrodon sp. – Schoch & Milner (2000: 72).

Holotype: SAM-PK-4010, an almost complete and well-preserved skull without mandible, where only the area around the right orbit is missing ( Fig. 6A–D View Figure 6 ).

Type locality and horizon: Farm Ferndale, Graaff-Reinet District (Eastern Cape Province, South Africa), Dicynodon Assemblage Zone (‘ Cistecephalus zone’ sensu Haughton, 1925: 236), Lopingian ( Rubidge et al., 2013).

Remarks: Romer suggested that L. watsoni might be synonymized with U. senekalensis van Hoepen ( Romer, 1947: 200) . Schoch & Milner (2000) considered the specimen as a Rhinesuchidae insertae sedis ( Schoch & Milner, 2000: 74) and Laccosaurus as a synonym of Uranocentrodon van Hoepen ( Schoch & Milner, 2000: 72) . In contrast, Damiani & Rubidge (2003) regarded L. insperatus as valid taxon.

Status: In the present study and in agreement to Damiani & Rubidge (2003), L. watsoni is considered a valid taxon.

Diagnosis: Medium-sized rhinesuchid with relatively short snout (preorbital distance approximately two times the postorbital), characterized by the following combination of derived character states: well-developed sensory sulci, infra-orbital sulcus with a step/Slike flexure between the orbit and the naris; width of interpterygoid vacuity pair greater than 90% of their length; vomers with field of denticles in symmetrical raised patches medially to the choanae; straight transverse vomerine tooth row; quadrate condyles projected behind the tip of the tabular horns; parasphenoid plate subrectangular, longer than wide, with a flat ventral surface; well-developed ‘pockets’, close to each other, thus the cristae musculares converge in the midline.