A relatively common, colourful and impressive hawker (not mosaic!) the males of which tend to patrol tirelessly above their patch of water. Contrast its bright green thorax with the dull brown thorax of Anax parthenope (the Lesser Emperor).
- Plain green thorax (both sexes)
- Yellow costa
- Irregular but solid black line down top of abdomen (both sexes)
- Abdomen colour: ♂-blue, ♀ – green or blue (confusingly!)