inferior longitudinal muscle of tongue inferior longitudinal muscle of tongue the inferior longitudinal muscle of tongue is an intrinsic muscle of the tongue. it is situated on the under surface of the tongue between the genioglossus and hyoglossus. it is innervated by the hypoglossal nerve (cranial nerve xii). its contraction shortens and thickens the tongue. inferior longitudinal muscle of tonguecoronal section of tongue, showing intrinsic muscles.the mouth cavity. (longitudinalis inferior labeled at bottom left.)detailsoriginroot of tongueinsertionapex of tonguenervehypoglossal nerve (cn xii)actionsretracts tongue with superior longitudinal muscle, making tongue short and thickidentifierslatinmusculus longitudinalis inferior linguaeta98a05.1.04.107ta22123fma46694anatomical terms of muscle structure the inferior longitudinal muscle of the tongue is an intrinsic muscle of the tongue. it is thin and oval in cross-section. it is situated between the paramedian septum, and the lateral septum. it extends from the root to the apex of the tongue. posteriorly, some of its fibers attach onto the body of the hyoid bone. anteriorly, its fibres blend with those of the styloglossus, hyoglossus, and genioglossus to form the ventral area of the tip of the tongue. innervation the inferior longitudinal muscle of the tongue is supplied by the hypoglossal nerve (cn xii). function contraciton of the inferior longitudinal muscle of the tongue shortens and thickens the tongue. additional images