Anax immaculifrons,[2] the magnificent emperor,[1] or blue darner,[3] is a species of dragonfly in the family Aeshnidae.

Almost all its range is in West and South Asia (the population further east in Asia is now recognized as a separate species, A. aurantiacus); it is Europe's largest dragonfly but very marginal in the continent where restricted to some Aegean Islands and Cyprus.

[5][7] It is a large, bluish green dragonfly with sapphire-blue eyes, bluish-green thorax, and pale reddish-brown abdomen marked with black.

Its thorax is pale bluish-green on dorsum with a blackish-brown mid-dorsal carina and turquoise-blue laterally.

[6] A. immaculifrons is found near slow flowing hill or mountain streams where it breeds.