1. Antenna with 13 segments (Fig. 2); hind tibia with 1 spur; anterior branch of dorsal lobe of gonostylus not as below...... 2
- Antenna with 15 segments; hind tibia with 2 spurs; anterior branch of dorsal lobe of gonostylus nearly straight, with a row of black spiny bristles at anterior margin (Kitakami 1937).................................... P. taiwanensis Kitakami
2. Flagellomeres about 1.5 –2.0 times as long as wide; cercus with distal margin of each lobe concave medially; dorsal lobe of gonostylus finger-like; ventral lobe of gonostylus bilobate, dorsal portion finger-like, ventral portion L-shaped (Figs. 4–5)................................................................................... P. emeishanensis sp. nov.
- Flagellomeres about 2.8–3.2 times as long as wide; cercus with distal margin of each lobe rounded medially; dorsal lobe of gonostylus with blunt setose medial projection at base, apex of lobe slender; ventral lobe of gonostylus not bilobate, with base narrow, apex wide and round (Figs. 9–10).................................................. P. levanidovae Zwick