Distinguishing characteristics and flight behaviourĭragonfly species (Anisoptera) are characterized by long bodies with two narrow pairs of intricately veined, membranous wings that, while generally transparent, may have coloured markings. Unlike damselflies, the front and rear wing pairs are shaped differently. In addition, dragonflies rest with their wings spread horizontally, rather than held vertically against each other (with the exception of one very small family, Epiophlebiidae). Dragonflies have a more powerful build and are generally much stronger fliers than damselflies. The globe skimmer (or wandering glider, Pantala flavescens), a migratory dragonfly, for example, makes an annual multigenerational journey of some 18,000 km (about 11,200 miles) to complete the migration, individual globe skimmers fly more than 6,000 km (3,730 miles)-one of the farthest known migrations of all insect species. Dragonflies also have huge bulging eyes that occupy most of the head, giving some a field of vision approaching 360 degrees. Slow-motion animation demonstrates how a dragonfly larva extends its labial mask to capture prey. Young dragonflies, called larvae or sometimes nymphs or naiads, are aquatic and are as dedicated predators under water as the adults are in the air. The functionally wingless larvae are usually mottled or dull in colour, matching the sediments or water plants among which they live. They have bulging eyes somewhat similar to the adults, but possess a formidable anatomical structure not present in the adult. Called the “ mask,” it is a fusion of the larva’s third pair of mouthparts. Disproportionately large, the mask folds beneath both the head and thorax when it is not in use. At the end of the mask is a set of fanglike pincers used to seize prey such as worms, crustaceans, tadpoles, and small fish. Different species of dragonfly larvae can be described as sprawlers, burrowers, hiders, or claspers. Their shape, metabolism, and respiration differ concordantly with the microhabitat they occupy.Ī dragonfly larva captures a fish by extending its labial mask. Larvae crawl from eggs laid in or near water. Some species lay their eggs inside plant tissue, others attach their eggs to substrates at or above the water’s surface, and some may drop or wash their eggs from their abdomen onto water.
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