Key to species of Cystomutilla and Hemutilla

1. Male (unknown in Hemutilla bifurcata and H. cheni)....................................................... 2

- Female (unknown in Hemutilla ferrugineipes, H. granulata, H. hoozana, and H. tuberculata)......................... 7

2. Clypeus flat or slightly concave. First metasomal tergum 1.1–1.3 × as long as broad. Length of volsella 0.5 × length of gonostylus (Figs 3 A–D). Cystomutilla André. ................................................................. 3

- Clypeus deeply concave. First metasomal tergum 1.6–2.0 × as long as broad. Length of volsella 0.65 × or more length of gonostylus (Figs 9 A–D, 10A–D). Hemutilla gen. nov. ........................................................... 4

3. Mesosternum midway to anterior margin mesally with two median weak curved carinae. Fore wing hyaline, not infuscated. Gonostylus mesally with few sparse short setae.............................................. C. ruficeps (Smith)

- Mesosternum midway to anterior margin mesally with distinct paired sharp tubercles. Fore wing infuscated. Gonostylus mesally with tuft of strong setae.......................................................... C. teranishii Mickel

4. Mandible apically bidentate. Metasomal sternum 2 without distinct lateral felt line (with a few short setae only). Hind coxa mesally with acute tubercle............................................................ H. tuberculata sp. nov.

- Mandible apically tridentate. Metasomal sternum 2 with distinct lateral felt line. Hind coxa mesally without acute tubercle, at most weakly swollen................................................................................ 5

5. Metasomal sternum 2 with short lateral felt line (length 0.5 × distance between line and posterior border of sternum). Legs and metasomal segment 1 ferruginous-red................................................. H. ferrugineipes sp. nov.

- Metasomal sternum 2 with well developed lateral felt line (length equal to or more than distance between line and posterior border of sternum). Legs and metasomal segment 1 black................................................... 6

6. Lateral section of clypeus concave, coarsely punctate. Mandible beneath basally slightly widened, rounded. Volsellar cuspis mesally with short setae (Figs 10 A–B)................................................... H. hoozana (Zavattari)

- Lateral section of clypeus not concave, granulate. Mandible beneath basally strongly widened. Volsellar cuspis mesally with long setae (Figs 9 A–B)............................................................... H. granulata sp. nov.

7. Mesopleuron smooth with large punctures along vertical narrow ridge; propodeum laterally and metapleuron micropunctate, mixed with sparse large punctures. Metasternal posterior median process acuminate or rounded. Metasomal sternum 1 with simple longitudinal carina. Cystomutilla André. .......................................................... 8

- Mesopleuron, metapleuron and propodeum laterally densely punctate. Metasternal posterior median process bifurcate. Metasomal sternum 1 with bifurcate carina. Hemutilla gen. nov. ................................................. 9

8. Head ferruginous-red. Metasomal tergum 1 posteriorly with median tuft and lateral fringe of white setae...................................................................................................... C. ruficeps (Smith)

- Head black. Metasomal tergum 1 posteriorly with fringe of white setae, without median tuft......... C. teranishii Mickel

9. Mesonotum laterally with lamellate carina from pronotal to mesonotal spiracle tubercles. Metasomal tergum 1 posteriorly with tuft of golden setae. Tergum 2 posteriorly and tergum 3 with about same length bands of golden setae.... H. cheni sp. nov.

- Mesonotum laterally lacking lamellate carina. Metasomal tergum 1 posteriorly with fringe of fuscous setae. Tergum 2 posteriorly and tergum 3 with bands of yellow setae, latter much longer than on tergum 2................. H. bifurcata (Chen)