Fig. 3 in The Cross River Gorillas: A Distinct Subspecies, Gorilla gorilla diehli Matschie 1904

Fig. 3. The skull of ZMUB 12789, the male holotype of G. diehli (Matschie, 1904) in A dorsal, B ventral, C anterior and D posterior views. Note the large wide and flat zygoma, the superoinferiorly wide zygomatic arch with only a mild mediolateral curvature, the perpendicular set of the zygoma relative to the zygomatic arch, the pronounced malar tubercles, and the inferomedial concavity of the zygoma circumscribing the infraorbital foramen (see also male paratypes in fig. 6).