prop it ia ▁as ▁a ▁valid ▁species , ▁while ▁Mik k ola , ▁La font aine ▁and ▁Kon onen ko ▁( 1 9 9 6 ) ▁placed ▁it ▁as ▁a ▁sub species ▁of ▁X est ia ▁spe ci osa . ▁ ▁The ▁wings pan ▁of ▁s sp . ▁spe ci osa ▁is ▁ 3 8 – 5 0   mm . ▁Sub species ▁ar ct ica ▁has ▁a ▁wings pan ▁of ▁ 3 6 – 4 5   mm . ▁Ad ult s ▁are ▁on ▁wing ▁from ▁June ▁to ▁August ▁in ▁one ▁generation . ▁ ▁The ▁lar va e ▁feed ▁on ▁various ▁low - g row ing ▁plants , ▁including ▁V acc in ium ▁my rt ill us , ▁L onic era ▁n ig ra ▁and ▁Bet ula ▁n ana . ▁ ▁Sub species ▁Note ▁that ▁only ▁spe ci osa , ▁ar ct ica ▁and ▁mod esta ▁are ▁confirmed ▁sub species . ▁The ▁other ▁listed ▁sub species ▁need ▁further ▁study ▁to ▁confirm ▁their ▁status . ▁X est ia ▁vir ides c ens ▁is ▁sometimes ▁included ▁here ▁as ▁another ▁sub species . ▁ ▁Gener ally ▁accepted ▁X est ia ▁spe ci osa ▁spe ci osa ▁( H üb ner , ▁ 1 8 1 3 ) ▁( G erm any ) ▁X est ia ▁spe ci osa ▁mod esta ▁( Al ps ) ▁X est ia ▁spe ci osa ▁ar ct ica ▁( Z etter sted t ▁ 1 8 3 9 ) ▁( nor thern ▁Europe , ▁northern ▁Canada ▁south ▁to ▁the ▁northern