Common whirligig beetle
The common whirligig beetle is a small, shiny black insect found primarily on the surface of calm freshwater ponds and lakes, particularly in Europe and Great Britain. Typically measuring about 1/4 inch (0.5 cm) in length, this beetle is notable for its agile movements, using its long front legs to grasp prey while its shorter legs propel it across the water. It possesses unique eyes that allow it to see both above and below the water simultaneously, aiding in its survival against predators such as larger insects, birds, and fish.
To evade threats, the common whirligig beetle can release a milky substance that clouds the water, providing a distraction during its escape. The beetle's diet mainly consists of insects and insect larvae, including mosquitoes, which it catches using its strong mandibles. Reproduction occurs in spring after hibernation, with females laying eggs in clusters on underwater plants. The larvae, upon hatching, are larger than adults and feed on midge larvae until they pupate and emerge as adults later in the summer. This lifecycle reflects the adaptability and success of the common whirligig beetle within its aquatic habitat.
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Common whirligig beetle
The common whirligig beetle is a shiny, black beetle which lives on the surface of calm ponds and lakes. It is mostly found in Europe. This beetle spends most of its time darting from place to place as it flees from predators and chases after prey.
Kingdom: Animalia
Phylum: Anthropoda
Class: Insecta
Order: Coleoptera
Family: Gyrinidae
Genus: Gyrinus
Species: Natator
The common whirligig beetle is an evolutionary success story. It's body shape and patterns of life reflect its ability to adapt to its environment. The common whirligig beetle typically grows to be about 1/4 of an inch (1/2 a centimeter) in length. This shiny, black beetle has six legs which extend from its thorax. Its front two legs are very long and are used for grasping food. Meanwhile, its short pairs of legs propel the common whirligig beetle across the surface of its aquatic habitat. This beetle is typically found living in groups on the surface of calm freshwater ponds and lakes throughout most of Great Britain and Europe. A single common whirligig beetle may jump more than three feet (one meter) across the water surface, a distance nearly 200 times its body length.
Like other insects, the common whirligig beetle has a head, thorax, and abdomen. Across its back, the common whirligig beetle has two wings which form hard outer cases called elytra. Underneath the two elytra is its pair of wings. All beetles have protective wing cases like the common whirligig beetle.
At the front of the common whirligig beetle's head are its biting and chewing mouthparts. Like many other creatures, the common whirligig beetle has a pair of mandibles which help it chew its food.
The common whirligig beetle uses its strong mandibles for chewing insects and insect larvae. This beetle often feeds on various species of mosquitos. The common whirligig beetle catches its prey with its large, pinching front legs. This beetle is able to see both above and below water at the same time because of the positioning of its eyes. As the common whirligig beetle floats along the water surface, its eyes are partially above the water and partially below the surface.
The common whirligig beetle is typically preyed upon by larger insects, birds, and fish. To protect itself, this insect produces a milky substance which it can release into the water. This substance acts as a sort of smoke screen. The milky substance causes the water to turn cloudy and gives the common whirligig beetle time to escape while the predator is distracted.
Adult whirligig beetles live in groups for protection. The hungriest members of the group can be found at the group's edges. More plentiful food can be found at the edges, but the risk of predators is greater.
Mating for the common whirligig beetle takes place in the spring, after the beetle has emerged from its hibernation period. The female common whirligig beetle lays her eggs in row-like clusters on underwater plants. The male then fertilizes these eggs. After several weeks, common whirligig beetle larvae hatch from these eggs. Each larva is about 1/2 inch (one centimeter) long. This is twice the size of an adult common whirligig beetle. Shortly after hatching, the common whirligig beetle larva begins to feed on tiny midge larvae. It is able to feed on these larvae using its canal-like mouthpiece. The larval beetle uses this mouthpiece to suck the fluid from the midge larvae.
As part of its development, the common whirligig beetle larva spins a cocoon around its body and continues to grow. During this stage the larva is long and thin with many gills. This stage is called the pupal stage. In August and September, a young common whirligig beetle emerges from its cocoon as an adult. It feeds for a while and then goes into hibernation. In the spring, when it awakes, it begins the mating process.
The life span of the common whirligig beetle is not known.
There are 700 species in the genus Gyrinus. Many are referred to as the whirligig beetle.
Bibliography
Brown, Paul. “Specieswatch: How Whirligig Beetles Evolved to Occupy an Environmental Niche.” The Guardian, 7 Sept. 2022, www.theguardian.com/environment/2022/sep/07/specieswatch-how-whirligig-beetles-evolved-to-occupy-an-environmental-niche. Accessed 9 Apr. 2024.
“Whirligig Beetle.” The Wildlife Trusts, www.wildlifetrusts.org/wildlife-explorer/invertebrates/beetles/whirligig-beetle. Accessed 9 Apr. 2024.
“Whirligig Beetle.” Australian Museum, 29 July 2022, australian.museum/learn/animals/insects/whirligig-beetle. Accessed 9 Apr. 2022.