Common Blue Skimmer
Scientific name: Orthetrum glaucum
Habitat: stream, marsh, pond, nullah
Body length: 42-51 mm
Distribution in Hong Kong: widespread, e.g.Tai Po Kau, Mui Wo, Cheung Chau
Flight period in Hong Kong: January to November
Similar species: Marsh Skimmer, Mangrove Skimmer, Lesser Blue Skimmer (Comparison)
Identification features (male):
1. Frons dark brown
2. Eyes dark blue
3. Synthorax dark blue in recently mature individual; Synthorax pruinose pale blue in aged individual
4. Amber spot on wingbase of hindwings
5. Abdomen mainly blue, black at the end
Identification features (female):
1. Synthorax and abdomen mainly yellowish brown
2. Two yellow stripes at two sides of synthorax; a disconnected yellow spot may appear at the end of the 1st stripe
3. Abdomen thinner than Lesser Blue Skimmer’s