The lesser petrosal nerve is a parasympathetic branch of the glossopharyngeal nerve.
Innervation
After the fibers of the lesser petrosal nerve have synapsed in the otic ganglion, it innervates the parotid gland, labial glands, and buccal glands.
Anatomical course
The lesser petrosal nerve originates in the tympanic cavity from the tympanic plexus. It enters the middle cranial fossa through the hiatus of the canal for the lesser petrosal nerve. From there, the lesser petrosal nerve courses parallel to the greater petrosal nerve in a ventral direction and reaches the inferior surface of the skull base through the sphenopetrosal fissure, where it joins the otic ganglion.