Elachista apina is a moth of the Elachistidae family. It is found in North America in British Columbia, Oregon and Washington. The length of the forewings is 4.8–5.7 millimetres (0.19–0.22 in). The costa in the basal eighth of the forewings is greyish brown. The wing is otherwise unicolorous white. The hindwings are white and the underside of the wings is silky light grey.