Eustachian tube passes between
The auditory tube passes between the large gap between the upper concave border of the superior constrictor and the base of the skull is semilunar and is known as the sinus of Morgagni. It is closed by the upper strong pa of the pharyngobasilar fascia. Ref: BD Chaurasia's HUMAN ANATOMY, Volume 3, 4th edition.
Superior and middle constrictors
Above superior constrictor
Middle and inferior constrictor
Below inferior constrictor
Head and neck