Description of the female of <i>Elachista leifi</i> (Lepidoptera: Elachistidae)

The female of Elachista leifi Kaila & Kerppola is described based on two females collected in northern Finland. In addition to the larger size; the almost black ground colour, the small light area at fringe at the tip of the forewing and the bluish lustre on the underside of the thorax are the best diagnostic characters. The female genitalia of the species can be separated from those of other closely related species, except E. kilmunella, by the shape of antrum, the teeth of ductus bursae and the size and shape of signum. We did not find any reliable differences in female genitalia between E. kilmunella and E. leifi, due to variation in the characteristics of E. kilmunella.