Key to Holarctias species of the Baikal region

1. Forewing with postmedial line not bent inward at costal margin; hindwing postmedial line without prominent inward curve between veins M1–M3 (Fig. 22D). In male genitalia (Figs. 42D–42F) socii large, near triangular; processes of juxta short, and not reaching middle of fibulae; aedeagus stout, with strong cornutus and without free hook-like process on apex. In female genitalia (Fig. 51D) ostium bursae comparatively narrow; antrum not twisted, widened laterally at middle.......................................................................................... H. rufinaria (Staudinger, 1861)

- Forewing with postmedial line bent inward at costal margin; hindwing postmedial line with prominent inward curve between veins M1–M3 (Fig. 23A). In male genitalia (Figs. 42G–42I) socii shorter than in H. rufinaria, lobe-like, with ventral short pointed spine; processes of juxta long and wide, reaching to 3/4 of length of fibula; aedeagus narrow, with long coecum, distally with long groove-like process. In female genitalia (Fig. 51E) ostium bursae wider than in H. rufinaria; antrum broad, open, twisted, anteriorly sharply narrowed into funnel-like shape, widening again after constriction.................................................................................................. H. rufinularia (Staudinger, 1901)