Scientific name: Onychargia atrocyana

Habitat: marsh

Body length: 28-35 mm

Distribution in Hong Kong: Scatteredly distributed in the New Territories and Lantau Island, e.g. Sha Lo Tung, Luk Keng, Mui Wo, Lamma Island

Flight period in Hong Kong: April to October

Identification features (male):

1. Frons with apparent chaetae

2. Two black stripes at two sides of synthorax respectively

3. Synthorax and the 8th to 10th abdominal segment pruinose white in mature male

Identification features (female):

1. Frons with apparent chaetae

2. Two black stripes at two sides of synthorax respectively