Thiotricha polyaula is a moth of the Gelechiidae family. It was described by Meyrick in 1918. It is found in India (Assam). The wingspan is 12-13 mm. The forewings are rather dark brown with the markings ochreous-white. There is a slender median streak from the base, branchingat one-fourth into two lines, the upper running to five-sixths but more or less widely interrupted in the middle, the lower running to three-fifths. There is a narrow pointed streak below the fold from the base to one-third and short subdorsal and dorsal lines from the base, as well as a pointed costal streak on the basal third, sometimes partially obsolete. A suffused dark fuscous tiansverse spot is found from the dorsum before the middle, immediately followed by a white longitudinal streak beneath the fold to the to