Key to the known males of the genus Olopachys

1. Opisthonotal setae J5 not reduced, long and needle-like (as in Fig. 1); cheliceral spermatodactyl relatively short and widened medially, leaf-like and obtusely pointed (Fig. 3); base of axillar seta pv1 and finger-like apophyse with separate position on femur II (Fig. 7)................................................................................. 2

- Opisthonotal setae J5 reduced, only vestigial microsetae present; cheliceral spermatodactyl relatively long and slim, without medial widening (with approximately parallel lateral margins), stiletto-like to blade-like and sharply tapered distally (Fig. 14); axillar seta pv1 of femur II with insertion on distinctive outgrowth, the outgrowth and finger-like apophyse with position on a common base (Fig. 13) .................................. 3

2. Two spur-like distal setae pl1 and pl2 on tarsus II present (Fig. 7); spermatodactyl obtusely pointed apically and shorter (less than 1.5 times as long as movable digit, Fig. 3); seta associated with petal-like palptibial outgrowth well developed and subequal in length to the outgrowth (Fig. 6); length of dorsal shield 635–675 µm ........................................................................................................ O . gronychi sp. nov.

- One spur-like distal seta pl1 on tarsus II present (as in Fig. 13); spermatodactyl truncate apically and longer (more than 1.5 times as long as movable digit); seta associated with petal-like palptibial outgrowth conspicuously shortened and with tip not reaching the middle of the outgrowth; length of dorsal shield 750 µm .............................................................................................................. O . crassipes Koroleva, 1976

3. Posterolateral margin of dorsal shield with 1 hypertrophied slot-like pore close to seta S4 (gdS4); palptibia with 3 smaller protuberances; length of dorsal shield 440–510 µm ............. O . vysotskajae Koroleva, 1976

- Posterolateral margin of dorsal shield with 2 adjacent hypertrophied pores between setae S4 and Z2 (gdZ1, gdS4); palptibia with 1 larger protuberance; length of dorsal shield 560–610 µm ........................... ............................................................................................................................... O . sklari Koroleva, 1976