Hezao belongs to the Aldrovanda Monti genus of the Droseraceae Family, with the Latin name of Aldrovanda vesiculosa. It originally grows in India and Australia, while in China it's mainly distributed in Heilongjian Province in the northeast of China.

Hezao is a sort of afloat or submerged herbaceous insectivorous plant. It bears single or furcation stems. There are 6 to 9 leaf whorls borne on a eustipes. There are complicated sensitive setae on the surface of a leaf. There are several cirruses on the upper part of the wedgy petiole. The ovoid leaves can open and close freely. When any algae or insects touch the setae on the leaf, the leaf blade can wrap them inside as food by closing up its both sides with the midrib as axis. Then the vein hair close to the midrib secretes digestive juice to digest the foods and then absorb them.

Hezao has no root and can grow by floating in water freely. It possesses chlorophyl, which can photosynthesize to produce alimentation for itself.