Large, swift-flying dragonflies, usually marked with blue, green or yellow. Adults hunt tirelessly for insects over ponds, lakes and streams, and wander widely in search of prey. Most species rest in a vertical position, but a few sit flat on the ground. Females have a prominent ovipositor and lay eggs in water plants or floating wood above or below the water line. Larvae are slender and sleek, with flat labia lacking bristles; they are rapacious hunters among water plants. Recently, A. californica and A. multicolor have been transferred from Aeshna to Rhionaeschna.
The largest Mosaic Darner in Canada and one of the most often encountered dragonflies in the northern forests of North America. In southern B.C., it lives at all elevations, but is most common around forest lakes at mid and high elevations. Prefers lakeshores with little emergent vegetation; it also occurs in deep fens and bogs, and around lakes and ponds surrounded by sedges. It may fly early in the morning and in the evening when the temperature is cool and the light is low. It likes perching on tree trunks.