Key to species (males) of Fistulatus (modified from Lu & Zhang, 2014)

1 Pygofer with two pairs of processes (Fig. 35)............................................................... 2

- Pygofer with one pair of processes (Fig. 6)................................................................. 5

2 Aedeagal shaft with one or more processes in distal half; pygofer processes extended mesad......................... 3

- Aedeagal shaft without processes in distal half (Figs 38–39); pygofer processes extended distad (Fig. 35)....... F. luteolus

3 Aedeagal shaft with pair of short, slender preapical processes (Figs 57–59)......................... F. quadrispinosus

- Aedeagal shaft with process or process flangelike............................................................ 4

4 Aedeagal shaft with a pair of short apical lateral processes (Figs 28–29); ventral process of pygofer side extended toward base (Fig. 25)................................................................................. F. biconjugara

- Aedeagal shaft with one dorsal preapical process (Figs 33–34); ventral process of pygofer extended toward apex (Fig. 30)........................................................................................ F. brevimarginalis

5 Aedeagal shaft with one pair of processes or flanges.......................................................... 6

- Aedeagal shaft with two pairs of processes (Fig. 24)................................................ F. bidentatus

6 Aedeagal shaft with spikelike lateral preapical processes (Figs 10–13)........................................... 7

- Aedeagal shaft not as above (Figs 17–18, 42–43, 48)......................................................... 8

7 Aedeagal shaft with hammer-shaped apex in lateral view (Fig. 12)............................. F. motuoensis sp. nov.

- Aedeagal shaft with somewhat digitate apex in lateral view (Fig. 54).................................... F. sinensis

8 Pygofer with processes directed medially (Fig. 45); aedeagus with shaft relatively straight in lateral view (Fig. 49).................................................................................................. F. rectilineus

- Pygofer with processes directed ventrally (Fig. 40); aedeagus with shaft curved dorsally in lateral view (Fig. 44).......... 9

9 Connective with lateral processes (Fig. 16); style with apical process slightly curved laterally, digitate (Fig. 15)... F. athena

- Connective without lateral processes; style with apical process strongly curved laterally, foot-like (Fig. 41)..................................................................................................... F. monkoboensis