A Diaspore is the dispersed unit, and includes structures such as wings, pappus hairs and elaiosomes in addition to the true seed. However, diaspores are often referred to as seeds in the literature, especially in cases such as the achenes of Asteraceae, where the maternal tissue fused to the seed coat cannot be readily distinguished from the true seed. Diaspore mass is often used in studies of dispersal and seed predation, as the diaspore is the unit that must be transported or handled by dispersal agents and predators.