| tympanic plexus|
| otic ganglion|
nervus petrosus minor
The lesser petrosal nerve (also known as the small superficial petrosal nerve) is the General visceral efferent (GVE) component of the glossopharyngeal nerve (CN IX), carrying parasympathetic pre-ganglionic fibers from the tympanic plexus to the parotid gland. It synapses in the Otic ganglion, from where the post-ganglionic fibers emerge.
Lesser petrosal nerve Wikipedia
After arising in the tympanic plexus, the lesser petrosal nerve passes forward and then through the hiatus for lesser petrosal nerve on the anterior surface of the petrous part of the temporal bone into the middle cranial fossa. It travels across the floor of the middle cranial fossa, then exits the skull via foramen ovale to reach the infratemporal fossa. The fibres synapse in the otic ganglion, and post-ganglionic fibres then travel briefly with the auriculotemporal nerve (a branch of V3) before entering the body of the parotid gland.
The lesser petrosal nerve will distribute its parasympathetic post-ganglionic (GVE) fibers to the parotid gland via the intraparotid plexus (or parotid plexus), the branches from the facial nerve in the parotid gland.
The nucleus of the lesser petrosal nerve is the inferior salivatory nucleus.
The facial nerve gives off a branch at the geniculate ganglion for communication with the otic ganglion which joins the lesser petrosal nerve.