Those that swim on the surface of ponds and lakes, such as whirligig beetles, have divided eyes that give the appearance of two pairs—the top half sees above water, the lower half sees below. The rowing legs lack claws but are fringed with long hairs. Size: Adult beetles of some species reach sizes up to 20 mm. The environments in which many whirligig beetles species are known to live. Donald A. Yee, Siegfried Kehl, in Thorp and Covich's Freshwater Invertebrates (Fourth Edition), 2015. Their bodies are oval, flattened, and metallic bluish black in colour. Movement: Swimmers using middle and hind pairs of legs as oars. In common with many aquatic insects, they use counter-shading to blend with their environment; they are black against a dark background when viewed from above, and their underbelly is pale against the sky when viewed from below. They get their common name from their habit of swimming rapidly in circles when alarmed and are also notable for their divided eyes which can … Whirligig beetle, (family Gyrinidae), any of about 700 species of beetles (insect order Coleoptera) that are widespread throughout the world and are usually seen in groups, spinning and whirling around on the surfaces of quiet ponds or lakes.Whirligig beetles prey on insects and other creatures that fall on the water surface. Life cycle: Whirligig beetles undergo complete metamorphosis. Whirligig beetles swim exceptionally fast in circles. Select an environment to see its whirligig beetles species checklist. Whirligig Beetles live on the surface of the water, often in large groups, gyrating as they search for prey, hence the common name. The whirligig beetles have compound eyes, and it looks at first as if there are four of them. These are water beetles that normally live on the surface of the water. Whirligig beetles have other tricks that reduce their likelihood of becoming fish or bird food. Gyrinidae Latreille, 1810 (Whirligig Beetles) Whirligig beetles live in lentic or lotic habitats and generally swim on the water surface if undisturbed, but they dive quickly if alarmed. In reality, there are two, both split across the middle. The backswimmer's coloration is the opposite of most insects, presumably because they live their lives upside down. Whirligig beetles are like the ducks of the arthropod world in that sense that they have conquered land, water and sky: they’re exceptional swimmers both above and below the water’s surface, and they have wings so they can fly to a new body of water if need be (which explains how that beetle got in the swimming pool). whirligig beetles Habitats. Gyrinids (the whirligig beetles) are those beetles that you’ve probably seen scurrying in groups across the surface of a pond. Morphologically, they’re quite different from hydrophilids and dytiscids – they’re adapted to life on the water surface, but they are adept at swimming below the water’s surface too. When they are large enough to pupate, they do so either underwater, still attached to stones, or in the soil near the stream. Udo Schmidt cc-by-sa-2.0 Whirligig Beetle … When they emerge as adult beetles, their mission is to locate the opposite sex, mate, and lay eggs; they don’t live long as adults. Some examples: Beetles that hunt, such as ground beetles, and those that use their sight for finding mates, such as fireflies, have larger eyes. Beetles that are aquatic in all life stages include ‘Whirligig Beetles’ (Gyrinidae). These aquatic insects use their long back legs as oars to propel themselves across the water. The larvae may take more than a year to mature. Whirligig beetles are found on the water surface of ponds and slow sections of streams and rivers. It can be found on almost any body of water from ponds and lakes, to canals, ditches and slow-flowing rivers. The Whirligig beetle is one of a group of 12 very similar species. The backswimmer's dorsal side is convex and V-shaped, like the keel of a boat.