Lesion of facial nerve at level of stylomastoid foramen leads to:

Involvement of "chordatympanic nerve" near its point of origin in the facial canal is accompanied by paralysis of motor, gustatory and autonomic functions of nerve. Involvement of nerve after the level of stylomastoid foramen (Eg: sarcoidosis of parotid, melkerson rosenthal syndrome) results in paralysis of facial muscles without dysguesia.