For example, the Gomphidae (clubtails) live in running water, and the Libellulidae (skimmers) live in still water. Some species prefer flowing waters, while others prefer standing water. Habitatĭragonflies as a group occupy a considerable variety of habitats, but many species, and some families, have their own specific environmental requirements. Some aeshnids such as the brown hawker ( Aeshna grandis) have translucent, pale yellow wings.ĭragonfly nymphs are usually a well-camouflaged blend of dull brown, green, and grey. In the chasers ( Libellulidae), however, many genera have areas of color on the wings: for example, groundlings ( Brachythemis) have brown bands on all four wings, while some scarlets ( Crocothemis) and dropwings ( Trithemis) have bright orange patches at the wing bases. The wings of dragonflies are generally clear, apart from the dark veins and pterostigmata. Freshly emerged adults, known as tenerals, are often pale-colored and obtain their typical colors after a few days, some have their bodies covered with a pale blue, waxy powderiness called pruinosity it wears off when scraped during mating, leaving darker areas Greens often combine a structural blue with a yellow pigment. Blues are typically created by microstructures in the cuticle that reflect blue light. Their overall coloration is often a combination of yellow, red, brown, and black pigments, with structural colors. Many adult dragonflies have brilliant iridescent or metallic colors produced by structural coloration, making them conspicuous in flight. Water is pumped in and out of the abdomen through an opening at the tip. Whereas damselfly nymphs have three feathery external gills, dragonfly nymphs have internal gills, located around the fourth and fifth abdominal segments. This labium is folded under the body at rest and struck out at great speed by hydraulic pressure created by the abdominal muscles. The lower jaw has a huge, extensible labium, armed with hooks and spines, which is used for catching prey. The general body plan is similar to that of an adult, but the nymph lacks wings and reproductive organs. The first instar is known as a prolarva, a relatively inactive stage from which it quickly moults into the more active nymphal form. The abdomen is long and slender and consists of 10 segments and a terminal appendage-bearing segment.ĭragonfly nymphs vary in form with species and are loosely classed into claspers, sprawlers, hiders, and burrowers. The legs are rarely used for walking, but are used to catch and hold prey, for perching, and for climbing on plants. In most large species of dragonflies, the wings of females are shorter and broader than those of males. The hindwings are broader than the forewings and the venation is different at the base. The wings are long, veined, and membranous, narrower at the tip and wider at the base. The thorax bears two pairs of wings and three pairs of legs. The mesothorax and metathorax are fused into a rigid, box-like structure with internal bracing, and provides a robust attachment for the powerful wing muscles inside it. The prothorax is small and is flattened dorsally into a shield-like disc which has two transverse ridges. The thorax consists of three segments as in all insects. The mouthparts are adapted for biting with a toothed jaw the flap-like labrum, at the front of the mouth, can be shot rapidly forward to catch prey. Also, they have three simple eyes or ocelli. It is dominated by the two compound eyes, which cover most of its surface. The head is large with very short antennae. It has a chitinous exoskeleton of hard plates held together with flexible membranes. By contrast, damselflies (suborder Zygoptera) have slender bodies and fly more weakly most species fold their wings over the abdomen when stationary, and the eyes are well separated on the sides of the head.Īn adult dragonfly has three distinct segments, the head, thorax, and abdomen as in all insects. Dragonflies and Damselflies Dragonflies ( Anisoptera) and Damselflies ( Zygoptera)ĭragonflies (suborder Anisoptera) are heavy-bodied, strong-flying insects that hold their wings horizontally both in flight and at rest.
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