Galls formed by Tanaostigmodes tychii look the same as the galls of T. tescus. Although LaSalle's drawings of the two galls [on pg. 173] have slight differences, Figures 173 and 171 both show an oval swelling to one side of the stem, with the only differences being: the width of the stem, the angle of view, and an exit hole visible in one figure but not the other.

The integral stem gall mistakenly described by Felt in 1940 as one of the two T. howardii galls [and previously appearing under the name "Tanaostigmodes howardii (integral stem)" on Gallformers] is either a T. tychii or a T. tescus gall, LaSalle explains.