Very little specific information is available about the biology of Edmund’s snaketail, although it is presumed to spend much of its time among trees and patches of vegetation. The larvae of this species have been recorded in highly oxygenated riffles (3).
Dragonfly larvae are highly mobile aquatic predators, feeding on a wide variety of aquatic prey, including minute crustaceans and other invertebrates. The larvae stalk their prey, locating it mainly by sight. Once it is close enough, they catch their prey by shooting out their lower jaw, using pressure that has built up in the muscles (7) (8). The lower jaw, called the labium, has hinged hooks which grasp the prey and drag it back to the mouth as the jaw retracts (7).
The length of the larval stage varies between species, although it may range from a few weeks to several years. During this time, the larvae undergo a series of moults, passing through several developmental stages known as instars or stadia (7) (8). Shortly before the final moult, the dragonfly larvae stop feeding and move to sites where they can emerge, usually in vegetation. The larvae emerge from their final moult having metamorphosed into adult dragonflies, with characteristic features such as wings and enlarged compound eyes (7). The wings of the newly emerged adult rapidly expand and harden, with the first flight occurring soon after the final moult (7) (8). The new dragonflies then leave the water, spending anything from a few days to several weeks feeding and maturing (7).
Adult dragonflies are agile, opportunistic predators with exceptional eyesight, preying on a wide variety of flying insects. Following the maturation period, adult male dragonflies return to the water, with many species setting up territories which are aggressively defended against other males. Female dragonflies typically only return to water to mate (7) (8).
Mating dragonflies adopt a characteristic ‘wheel’ position, with the male grasping the female by the head using claspers on the end of the abdomen, while the female bends the tip of her abdomen forward to reach the male genitalia on the second and third segments of the male’s abdomen (7) (8). The female typically lays eggs almost immediately after mating, and is often guarded by the male (7).