| any of numerous aquatic beetles of the family Gyrinidae, commonly seen in groups circling about rapidly on the surface of the water. |
| whirligig beetle n. Any of various gregarious beetles of the family Gyrinidae that circle about rapidly on the surface of water. |
whirligig beetle
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. Their bodies are oval, flattened, and metallic bluish black in colour. The front legs are long and slim, while the middle and hind pairs are short and flattened and function as oars. They can dive and swim underwater when attacked. The compound eyes are divided, making them appear to have two pairs of compound eyes, one above and one below the water surface. They have well-developed wings and can fly well.
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