Key to the species of Phygasia in Taiwan

1 Penis longer (Fig. 16) (4.6 times longer than wide), pronotum finely wrinkled; apex of pump of spermatheca pointed (Fig. 22)......................................................................................... P. ornata Baly

- Penis shorter (Figs 14, 15) (<4.6 times longer than wide), pronotum smooth, apex of pump of spermatheca rounded (Figs 20, 21)................................................................................................. 2

2 Antenna, tibia, and tarsus yellowish-brown or brown; penis (Fig. 15) 4.3 times longer than wide, sternite VIII long (Fig. 24).......................................................................................... P. diluta Chûjô Antenna, tibia, and tarsus black; penis (Fig. 14) 3.9 times longer than wide, ternite VIII short (Fig. 23) P. chengi, new species