New Nipponentomon species from northern Asia (Protura: Acerentomata, Nipponentomidae).

Nipponentomnon imadatei sp. nov. from Northeast China and Nippon entomon taiga sp. nov. from Siberia, Russia are described. Nipponentornon heterothrixi Yin & Xie is redescribed based on type materials and lectotype and paralectotypes are designed for the species. Nipponentonon bidentatumn and N. nippon are reported for the first time from China. Nipponentornon imnadatei sp. nov. is characterized by a short labrum, absence of seta Pla on tergite VII and presence of three A-setae on sternites IV-VI. It is similar to N. jaceki from the Russian Far East, but differs in the shape of the comb, shape of setaβ1 on the foretarsus, length of sensillum e on the foretarsus, and in chaetotaxy on tergite I and sternites IV-VI. Nipponentomnon taiga sp. nov. is characterized by a short labrum, presence of seta P2a' on nota, seta P0a on tergite I, seta Pla on tergites I-VII, and absence of seta P3a on tergites II-VII. It is similar to N. heterothrixi, but differs in absence of seta d6 on the head, shape of accessory setae on tergites VI and VII, long and setiform setaβ1, and shorter sensilla c, e, g, a' and c' on the foretarsus than in sensilla in N. heterothrixi and in the porotaxy. A key for the world species of the genus is provided and the porotaxy of five species is reported in detail.