Erythromma najas, the red-eyed damselfly, is a member of the Coenagrionidae family of damselflies.
The species is a small damselfly, 35mm long, predominantly black with iridescent blue markings. The male resembles blue-tailed damselflies (Ischnura species) but is distinguished by its large, spaced eyes that are a deep red. It is very similar to the small red-eyed damselfly (Erythromma viridulum).
Males typically spend much of their time perched on the leaves of floating vegetation such as water lilies or mats of algae.