1	Dorsal habitus completely black and shiny; elytral costae markedly elevated and visible; general dorsal sculpture dense and deep; body length 14–22 mm, larger than all other species; distribution: west coast lowlands of Western and Northern Cape	X. shuckardi Burmeister, 1842 (Fig. 3)
–	Dorsal habitus black or brown and matte or velutinous; elytral costae weakly elevated and dorsal sculpture scattered and shallow; body length 11–16 mm	2
2	Dorsal habitus exhibiting cretaceous markings	3
–	Body without cretaceous markings	4
3	Cretaceous ornamentation extensive on elytral surface, pronotal margins and protruding areas of abdominal sternites; body covered in long, scattered black setae; distribution: high mountains of Eastern Cape Karoo, above Great Escarpment	X. sneeubergensis Perissinotto, Villet & Stobbia, 2003 (Fig. 10)
–	Cretaceous markings moderately developed on pronotal margins and occasionally present also on elytra, but very faintly; body velutinous and covered in dense, medium to long golden-brown or orange setae; distribution: eastern areas of Eastern Cape Karoo	X. lenxuba Perissinotto, Villet & Stobbia, 2003 (Fig. 11)
4	Dorsal habitus completely black and matte; metatibial internal apical spine as long as spurs in both sexes; anterior clypeal margin weakly sinuate to straight; distribution: south-western Namibia and adjacent areas of Northern Cape	X. namibica Perissinotto, sp. nov. (Fig. 2)
–	Dorsal habitus black or brown to reddish-brown; metatibial spurs and particularly inner apical spine hypertrophic in male; anterior clypeal margin strongly sinuate; distribution: Cape Fold Belt of the Western and Eastern Cape provinces	X. braunsi Perissinotto & Šípek, sp. nov. (Figs 1, 8, 9)