StW 505 is the most complete hominin cranium discovered in Sterkfontein Member 4 since Broom's excavations.

It was found in situ in Member 4 breccia in 1989 and is larger, on the whole, than any other cranium from Sterkfontein that has comparable parts.

[1] Displacement due to breakage, as well as plastic deformation, has affected Stw 505 in several areas, especially the face and the vault.

In several areas the distinct anterior pillar, the straight inferior border of the zygoma, the pattern of cresting on the naso-alveolar clivus, the basal aspect of the temporal bone-Stw 505 closely matches the morphology of specimens of Australopithecus africanus and is distinct from other hominins.

Some isolated characters overlap with other groups, mainly early Homo and/or A. robustus.