Referred otalgia from base of tongue or oropharynx is carried by nerve:
The Jacobson nerve, tympanic branch of glossopharyngeal nerve (cranial nerve IX) directly innervates the ear but also has pharyngeal, lingual, and tonsillar branches to supply the posterior one-third poion of the tongue, tonsillar fossa, pharynx, eustachian tube, and parapharyngeal and retropharyngeal spaces. So any pathology involving those areas can lead to referred otalgia. Must know: Referred Otalgia: the source of the pain does not reside within the ear but, rather it originates from a source distant from the ear hence it is called as "referred otalgia". Any pathology residing within the sensory net of cranial nerves V, VII, IX, and X and upper cervical nerves C2 and C3 can potentially cause referred otalgia. Ref: Diseases of Ear Nose & Throat, by P L Dhingra, 2nd edition.
Cranial nerve V
Cranial nerve VII
Cranial nerve IX
Cranial nerve X