Key to Blastobasis species from Mainland China based on genitalia

1. Male............................................................................................... 2

- Female............................................................................................ 11

2. Dorsal part of valva with costal process bearing a row of elongate spine-like setae................................. 3

- Dorsal part of valva with costal process lacking elongate spine-like setae......................................... 5

3. Gnathos without denticles medially on posterior margin (Fig. 14)................................... B. sprotundalis

- Gnathos with two denticles medially on posterior margin..................................................... 4

4. Proximal flange bearing long setae along ventral margin, membrane above proximal flange with a row of elongate spine-like setae (Fig. 15)................................................................................. B. parki

- Proximal flange lacking long setae along ventral margin, membrane above proximal flange with a cluster of elongate spine-like setae (Fig. 16).............................................................................. B. drymosa

5. Phallus hooked apically (Fig. 23)......................................................... B. hamata, sp. nov.

- Phallus not hooked apically............................................................................. 6

6. Membrane above proximal flange with dense spine-like setae.................................................. 7

- Membrane above proximal flange without spine-like setae.................................................... 8

7. Anellus with one to two pairs of long spine-like setae apically (Fig. 21)......................... B. aciformis, sp. nov.

- Anellus without setae apically (Fig. 22)................................................... B. edentula, sp. nov.

8. Proximal flange with spine-like setae on outer margin........................................................ 9

- Proximal flange without spine-like setae on outer margin.................................................... 10

9. Proximal flange bearing an extremely long seta and a row of short spine-like setae on outer margin (Fig. 17)................................................................................................ B. spinisetosa, sp. nov.

- Proximal flange bearing a row of almost equally elongate spine-like setae on outer margin (Fig. 18)............ B. inouei

10. Membrane above proximal flange with dense setae on ventral 1/3 (Fig. 20)....................... B. divulgata, sp. nov.

- Membrane above proximal flange without setae (Fig. 19)..................................... B. adamskii, sp. nov.

11. Eighth sternum with a darkly pigmented posterior spot medially (Fig. 24)............................ B. sprotundalis

- Eighth sternum without darkly pigmented posterior spot medially............................................. 12

12. Intersegmental membrane posterior to seventh segment without an area of dense microtrichiae flanking ostium (Fig. 27)....................................................................................... B. adamskii, sp. nov.

- Intersegmental membrane posterior to seventh segment with an area of dense microtrichiae flanking ostium............ 13

13. Antrum distinctly broadened........................................................................... 14

- Antrum inconspicuous................................................................................ 15

14. Antrum weakly sclerotized (Fig. 29)..................................................... B. aciformis, sp. nov.

- Antrum membranous (Fig. 30).......................................................... B. edentula, sp. nov.

15. Microtrichiate area flanking ostium on intersegmental membrane posterior to seventh segment bulged and forming a process (Fig. 26).......................................................................... B. spinisetosa, sp. nov.

- Microtrichiate area flanking ostium on intersegmental membrane posterior to seventh segment not bulged............. 16

16. Seventh sternum concave in V-shape on posterior margin (Fig. 25)..................................... B. drymosa

- Seventh sternum concave in arc-shape on posterior margin (Fig. 28)........................... B. divulgata, sp. nov.