Key to the males of the species of Semia

1. Fore wing radial crossvein not parallel but about right-angled to outer margin of fore wing; timbal cover well developed, dis- tinctly longer than tergite 2.................................................... 2 ( S. klapperichi species group)

- Fore wing radial crossvein nearly parallel to outer margin of fore wing; timbal cover about as long as or shorter than tergite 2....................................................................................................3

2. Inner area of pronotum largely light coloured; uncal lobes with rounded apices........................... S. klapperichi

- Inner area of pronotum mostly black; uncal lobes with distinctly narrowed apices..................... S. magna sp. nov.

3. Body without median fascia continued from head to abdomen; uncal lobes without multiple spines.................... 4

- Body with median black to dark brown fascia continued from head to abdomen; uncal lobes with multiple spines on each lobe............................................................................................. S. spinosa

4. Uncal lobe without long extended projection protruding laterally from underside of uncus............................ 5

- Uncal lobe with long extended projection protruding laterally from underside of uncus, being laterally parallel to uncal lobe........................................................................................... S. gialaiensis

5. Hind wing with continuous infuscation along hind margins of apical cells 1–6.................................... 6

- Hind wing without continuous infuscation along hind margins of apical cells..................................... 7

6. Uncal lobes comparatively slender, with length about four times the width, tapering to subapex, with apex roundly expanded and slightly twisted longitudinally, in ventral view................................................. S. majuscula

– Uncal lobes comparatively broad, with length about three times the width, and parallel to each other from bases to truncated apices, in ventral view......................................................................... S. tibetensis

7. Uncal lobes very long, with length more than four times the central width........................................ 8

- Uncal lobes short, with length less than four times the central width............................................. 10

8. Abdominal tergite 8 covered with white pollinosity; uncal lobe in similar width from base to apex.....................9

- Abdominal tergite 8 without white pollinosity; uncal lobe with much widened apex.......................... S. lachna

9. Fore wing ulnar cell 2 comparatively long, with length more than four times the width; uncal lobes widened apically in lateral view; abdominal tergites 6 and 7 seldom covered with white pollinosity................................. S. watanabei

- Fore wing ulnar cell 2 comparatively short, with length less than four times the width; uncal lobes narrowed apically in lateral view; abdominal tergites 6 and 7 thickly covered with white pollinosity............................... S. hainanensis

10. Timbal cover moderately or well developed, with its anterior margin at similar level of or more anteriorly positioned than antero-median margin of tergite 2........................................................................ 11

- Timbal cover rudimentary, very short, with its anterior margin far behind (far more posteriorly positioned than) antero-median

margin of tergite 2.................................................................................. 12 11. Abdomen shorter than 1.6 times the length of head and thorax together; uncal lobes triangulate with narrowed apices, in ventral view.............................................................................. S. spiritus sp. nov. - Abdomen longer than 1.8 times the length of head and thorax together; uncal lobes wide, wider in apices than in bases, in ventral view............................................................................... S. pallida sp. nov.

12. Uncal lobes comparatively long, with length more than twice the width, nearly parallel to each other........................................................................................................ S. albusequi sp. nov.

- Uncal lobes very short, with length much less than twice the width, widely separated from each other........ S. brevidilata