Scientific name: Heliogomphus scorpio

Habitat: fast-flowing stream

Body length: 57-60 mm

Distribution in Hong Kong: Mainly in north and central New Territories, e.g. Sha Lo Tung, Hok Tau, Wu Kau Tang; also recorded in Gilwell Campsite in Kowloon

Flight period in Hong Kong: April to September

Identification features: 

1. Mesepisternum with a pair of “7”-shaped yellow spot in opposite direction

2. Three complete yellow stripes at two sides of synthorax respectively

3. The 7th abdominal segment with a large white spot

4. Superior anal appendage horn-like with a bent end in male