Indigo Dropwing

Scientific name: Trithemis festiva

Habitat: stream

Body length: 36-38 mm

Distribution in Hong Kong: Widespread, e.g. Tai Tam, Mui Wo, Cheung Chau 

Flight period in Hong Kong: February to December

Similar species: Black Marsh Skimmer (Comparison: male), Blue Chaser (Comparison: male), Crimson Dropwing (Comparison: female)

Identification features (male): 

1. Synthorax and the 1th to 3rd abdominal segment pruinose dark blue

2. Dorsum of abdomen without apparent black vertical stripes

3. Paired small yellow spots on the 4th to 7th abdominal segment for some individuals

Identification features (female): 

1. Synthorax and abdomen yellow

2. Dark-colored thick stripe on dorsal carina and dark-colored antehumeral stripe

3. Small area of yellowish brown spot at wingbase

4. Black vertical stripes on dorsum and two sides of abdomen

5. The 8th to 9th abdominal segment all black