Macromidia rapida Martin, 1907

Macromidia rapida, male, Huu Liên, June 2014

Martin (1907) erected the genus Macromidia to include the type species M. rapida Martin (from “Tonkin”, i.e. North Vietnam).

Another male, from Tam Dao

(remark: this photo has been taken after quite a long examination in hand, 
that’s why position of the wings looks unnatural - they should lie flat)

In 3 years, I bumped into M. rapida only 3 times, at rocky streams of Ba Vi and Tam Dao’s foothills, running through secondary forests. It is certainly not scarce but just inconspicuous - spend the great part of the day hiding in the vegetation.  

Two times, I found M. rapida resting at eye level amongst bushes, along moderate to fast flowing open/partially shaded rocky streams - one time inside willow-like shrubs in the middle of the stream.

The third time, an individual was netted as it was zigzagging low over a tiny, shallow pool at the margin of a stream, just before rain. Cat-like reflexes are needed to catch this little fellow!

(same remark as photo above)

Abdomen black, yellowish striped on the middorsal line.

Head largely dark reddish brown; frons dark metallic green, labium pale brownish. Narrow yellow stripe on the anteclypeus.
Synthorax shining metallic green and yellow laterally; dorsum (mesepisternum) metallic green with lower portion reddish brown.

 "Oh my god what happen to me !"

Tip of abdomen, dorsal.

Caudal appendages of typical Macromidia type, the superior yellowish with dark base and apex.

Tip of abdomen, lateral.

I didn’t spot the female, but according to Asahina (1988), head and thorax patterned as those of the male insect. Cerci yellowish with black type.

M. rapida is found in southern China, Thailand, Cambodia and Vietnam. This species inhabits streams of lowland/mid-elevation forests, even degraded ones (young secondary forest for example, as I saw at Ba Vi).