An anatomic variation of the stylomastoid foramen

During the examination of cranial bones, we observed an abnormality in one of the right temporal bones. In this variation, the stylomastoid foramen was not completely formed on the temporal bone and instead of a foramen, there was a sulcus in its localization on the bone. The articulation with the occipital bone transformed this sulcus into a foramen. This variation was not reported in the literature.