Elachista ischnella is a moth of the Elachistidae family that is found in Arizona, Colorado, New Mexico and Texas. The length of the forewings is 3.7–4.2 millimetres (0.15–0.17 in). The first 1/3 of the costa on the forewings is grey. The ground colour is white, densely dusted with brownish grey tips of scales. This dusting is weaker in the middle of the wing where there is an indistinct elongate dark grey streak at the fold. The hindwings are grey and the underside of the wings is also grey.