The host plant of this species is completely unknown. Larva hibernates in the first instar, feeding only the chorion in the autumn. In the spring 1998, there were several larvae in good condition, but they didn't accept any of the offered plants (incl. most bog plants of Ericaceae and Rosaceae). The host seems to be a Lapland-plant, not growing in the South, or less probably only some special parts of the food plant. One of my favorite guesses is Phyllodoce caerulea. Cassiope tetragona is not growing in Utsjoki; thus it simply cannot be the main host of Clossiana polaris.
Finland, InL: Utsjoki kk, ex ovo July 1997, Leg: K. Silvonen.
Photo © Kimmo Silvonen