part of part of Homo sapiens temporal bone bone foramen hiatus and groove of petrous part of temporal bone for lesser petrosal nerve 2026-03-19T00:00:00Z A bone foramen and associated groove on the anterior surface of the petrous part of the temporal bone, lying lateral to the hiatus for the greater petrosal nerve, through which the lesser petrosal nerve (a branch of CN IX) exits the middle ear and courses toward the foramen ovale to reach the parotid gland via the otic ganglion. David Osumi-Sutherland