Key to the males of the species of Mogannia Amyot & Serville from China

1. Basal half of fore wing brown or dark brown, outer margin of brown area with a wide reddish rim.............. M. effecta

- Basal half of fore wing not as above....................................................................... 2

2. Body lustrous metallic dark blue.......................................................................... 3

- Body lusterless and not bluish............................................................................ 4

3. Abdomen distinctly extended laterally in dorsal/ventral view; upper lobe of pygofer with apex rounded and curved dorsally in lateral view................................................................................. M. indigotea

- Abdomen not extended laterally in dorsal/ventral view; upper lobe of pygofer with apex acute and curved ventrally in lateral view......................................................................................... M. cyanea

4. Body green to yellowish brown; mesonotum bicolored, with dark brown to black patches medially..................... 5

- Body dark brown or black; mesonotum unicolored, or bicolored but with reddish ochraceous patches medially............ 8

5. Hind wing with a fuscous stripe on anal angle........................................................ M. basalis

- Hind wing without fuscous stripe on anal angle.............................................................. 6

6. Basal half of fore wing mostly hyaline, with a large oblique dark brown fascia overlapping nodal line........... M. obliqua

- Basal half of fore wing light yellow, without distinct fascia overlapping nodal line.................................. 7

7. Upper lobe of pygofer very short, slightly rounded, not forming a process........................... M. ruiliensis sp. n.

- Upper lobe of pygofer long, distinctly extended apically, forming a digitate process........................... M. hebes

8. Head and pronotum with dark ochraceous longitudinal median fascia............................................ 9

- Head and pronotum unicolored, without distinct longitudinal median fascia....................................... 12

9. Male pygofer with a slender accessory tooth between upper lobe and dorsal beak of pygofer...... M. guangdongensis sp. n.

- Male pygofer without accessory tooth.................................................................... 10

10. Distal shoulder of male pygofer remarkably convex near upper lobe, forming a large, somewhat triangular process in lateral view........................................................................................ M. hainana

- Distal shoulder of male pygofer slightly convex or straight near upper lobe....................................... 11

11. Ventral surface of abdomen and basal membrane of hind wings reddish ochraceous.......................... M. conica

- Ventral surface of abdomen and basal membrane of hind wings brown................................. M. mandarina

12. Abdomen not extended laterally in dorsal/ventral view; upper lobe of pygofer with apex remarkably extended forming a large, round lobe-like process................................................................ M. tumdactylina sp. n.

- Abdomen distinctly extended laterally in dorsal/ventral view; upper lobe of pygofer not as above..................... 13

13. Postclypeus distinctly longer than vertex in dorsal view; upper lobe of pygofer stout, with apex distinctly curved upwards in lateral view................................................................................... M. nasalis

- Postclypeus shorter than vertex in dorsal view; upper lobe of pygofer long and slender, with apex slightly curved downwards in lateral view....................................................................................... 14

14. Distance between eyes about as long as head in dorsal view.......................................... M. formosana

- Distance between eyes distinctly longer than head in dorsal view......................................... M. minuta