Stilt-legged Fly 微脚蝇 (Micropezidae)

"The Micropezidae are a moderate-sized family of acalyptrate muscoid flies in the insect order Diptera, comprising about 500 species in about 50 genera and 5 subfamilies worldwide, (except New Zealand and Macquarie Island).

Insects in this family are commonly called stilt-legged flies, after their characteristically long legs. The fore legs are markedly smaller than the other pairs. Mostly they are long-bodied, often black flies, usually with infuscated (darkened) wings. Wings are reduced in the genera Calycopteryx and entirely absent in the ant-like Badisis ambulans.

Very slender small to large size (3 mm-16 mm) flies with long thin legs and narrow wings. The head is small elongate or rounded. The antenna are small and the arista is bare or pubescent. Ocelli are present but ocellar bristles are absent. Vibrissae are absent and the postvertical bristles are divergent or absent. There are 0-3 pairs of frontal bristles, which curve forward or backward. Interfrontal bristles are absent. The wings are clear or with a smoky patterned. The costa is without interruptions. The subcosta is complete, its ending in the costa close to vein R1. The posterior basal wing cell and discoidal wing cell are sometimes fused. Crossvein BM-Cu present or (Micropezinae) absent. The abdomen is long and narrow. The tibiae lack a dorsal preapical bristle." - Wikipedia
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