Water scorpion | 台北市立動物園資訊網

water scorpion, any of the approximately 150 species of aquatic invertebrates of the family Nepidae (order Hemiptera). The water scorpion[1] resembles[2] a land scorpion in certain ways: it has scythelike front legs adapted for seizing prey and a long, thin, whiplike structure at its posterior end. This “tail,” made up of two attached respiratory tubes, is extended above the surface of the water, enabling the animal[3] to take in air. The bite of the water scorpion is painful but is far less harmful to humans than the sting of the true scorpion.

Water scorpions are blackish brown in colour and measure about 25 to 52 millimetres (1 to 2 inches) in length. The different species vary somewhat in shape. Those of the genus Nepa, for example, ha...