Syndyas, Loew. The, 1857

Grootaert, Patrick & Yang, Ding, 2009, A New Syndyas Loew, 1857 (Diptera: Hybotidae: Hybotinae) From Mangroves In Singapore, With A Review Of The Oriental And Australasian Species, Raffles Bulletin of Zoology 57 (1), pp. 17-24 : 18

KEY TO ORIENTAL AND AUSTRALASIAN SYNDYAS

1 Discal cell shorter than basal cells ...................................... 2

– Discal cell as long as basal cells ......................................... 4

2 Discal cell very short, basal cells nearly 3 times longer. ( Sri Lanka, Papua New Guinea) .............. S. parvicellulata Bezzi

– Discal cell longer ................................................................. 3

3 Basal cells about 1.5 times as long as discal cell. Mesonotum black, without blue shine. Abdomen not elongated ( Indonesia: Krakatau) .............................................. S. brevior de Meijere

– Basal cells almost as long as discal cell. Mesonotum black in ground-colour, with a blue shine. Abdomen long and slender ( Indonesia: Krakatau) ........................ S. elongata de Meijere

4 Tarsomeres 1 and 2 of all legs yellow (Taiwan) .................... ..................................................................... S. orientalis Frey

– All tarsomeres black ............................................................ 5

5 Wing clear ( India, Myanmar) ............. S. vitripennis Brunetti

– Wing not clear, but yellowish to brownish tinged ............. 6

6 Wing yellowish tinged, no stigma ( Philippines) ..................... ......................................................................... S. dapana Frey

– Wing brownish tinged, usually with stigma (except S. eumera ) ................................................................................. 7

7 Halter dark yellow, wing brown with dark brown stigma ( China: Zheijang) ....................................... S. sinensis Yang & Yang

– Halter black .......................................................................... 8

8 Brown stigma present. Hind femur club-shaped (less distinct in S. nigripes ) ....................................................................... 9

– No stigma present. Hind femur very thickened (thickest near middle) ( Papua New Guinea) ...................... S. eumera Bezzi

9 Veins R 4+5 and M are straight running parallel toward costa. Hind femur ventrally with a row of bristles (not spiny). ( Indonesia: Ceram) ............................................... S. aterrima de Meijere

– Veins R 4+5 and M converging towards wing tip, but turning up just before meeting the costa. Hind femur ventrally with a row of long spiny bristles ......................................................... 10

10 Hind femur strongly swollen (club-shaped). Tip of right epandrial lamella bifurcate, outer lobe bearing broad black bristly hairs ( Singapore) ............................. S. singaporensis , new species

– Hind femur weakly swollen. Tip of right epandrial lamella bifurcate, outer lobe with only ordinary hairs ( North Palaearctic , Oriental China – Guizhou, Hainan) ........................................ ........................................................... S. nigripes (Zetterstedt)