Key to species of Strophedra in China (based on male genitalia)

1. Phallus without a spine................................................................................ 2

- Phallus with a ventral spine or a distal denticle............................................................. 4

2. Tegumen with a pair of flaps on its lateral wall (Fig. 15)............................................ S. quercivora

- Tegumen without a pair of flaps on its lateral wall.......................................................... 3

3. Cucullus longer than 1/2 length of valva; phallus uniformly wide from base to 3/4, abruptly narrowed and almost uniform from distal 1/4 to apex (Fig. 16)....................................................................... S. magna

- Cucullus shorter than 1/2 length of valva; phallus tapering distally (Fig. 17)............................... S. nitidana

4. Phallus with a ventral spine............................................................................ 5

- Phallus with a distal denticle........................................................................... 6

5. Cornuti absent (Fig. 12)...................................................................... S. nigrifusca

- Cornuti composed a row of fine spines (Fig. 11)................................................ S. paraspinifera

6. Phallus with a denticle at distal 1/5, neck about 4/5 width of valva at base (Fig. 13)......................... S. laticolla

- Phallus with a denticle before apex, neck about 1/2 width of valva at base (Fig. 14)....................... S. tricornuta