Key to Scolothrips species from Japan (adult females)

1. Body strongly bicoloured, with red internal pigments before KOH treatment; fore wing dark at base (Fig. 2 A); metascutum with narrow spaced longitudinal lines of sculpture (Fig. 1 C).............................................. S. asura

-. Body uniformly white or yellowish white, often with greyish shadings but never bicoloured, without red internal pigments; fore wing hyaline at base (Fig. 4 A); metascutum with widely spaced transverse lines of sculpture or reticulation (Fig. 3 C)... 2

2. Pronotum with a pair of posteromedian discal setae (Fig. 3 A); abdominal tergites each with small greyish spots near anterior angles and transverse shadings between these spots (Fig. 4 B); abdominal tergite IX with small setae III (SS3) long, usually more than 75 μm (Fig. 4 C).................................................................. S. rhagebianus

-. Pronotum with no discal setae (Fig. 5 A); abdominal tergites often weakly shaded but never with such spots and markings; abdominal tergite IX with SS3 setae short, usually less than 35 μm (Fig. 6 D)............................. S. takahashii