Key to the subgenera of the genus Mixotrephes

1 Mesoscutellum coarsely sculptured, with strongly convex sides. Ventral abdominal carinae on sternites 2–6. – Male: Phallosoma short, pin-shaped, with round, unmodified apex. – Female: Sternum 7 short, round, unmodified, without strongly pigmented area. .......... ................................................................................................ Pictotrephes subgen. nov.

– Mesoscutellum finely punctured, with weakly convex sides. Ventral abdominal carinae on sternites 2–4(5). – Male: Phallosoma modified. – Female: Sternum 7 with posteromedial lobe and pigmented area. ................................................................................................ 2

2 Male: Pygophore with strongly developed spur. Phallosoma long, curved; apex beakshaped. – Female: Sternum 7 with distinct or less visible darkly pigmented area forming one caudomedial lobe. ................................ Mixotrephes Papáček, Štys & Tonner, 1989

– Male: Pygophore with reduced spur. Phallosoma short, uvula-shaped; apex upright and club-shaped. – Female: Sternum 7 with darkly pigmented area forming two caudomesal lobes or one caudomedial lobe. ........................ Thermotrephes Papáček & Zettel, 2006