Water Bug Trap

(Aldrovanda), a genus of insectivorous aquatic plants from the sundew family. The genus contains one species, Aldrovanda vesiculosa, with floating filiform stems and without roots. There are six to nine leaves in whorls, with long bristles on the apex of a broad petiole. The leaf folds in half lengthwise upon stimulation of the delicate hairs on its surface, and the edges come together. In this manner the water bug trap catches and then digests small aquatic larvae and crustaceans. The water bug trap is encountered sporadically in Western Europe, Africa, eastern Asia, Southeast Asia, and Australia. In the USSR it is found in the European portion, the Caucasus, the Far East, and Middle Asia, most often in the oxbow lakes.