An epiphyte is a plant that grows harmlessly upon another plant (such as a tree) and derives its moisture and nutrients from the air, rain, and sometimes from debris accumulating around it. Epiphytes differ from parasites in that epiphytes grow on other plants for physical support and do not necessarily negatively affect the host. An epiphytic organism that is not a plant is called an epibiont. Epiphytes are usually found in the temperate zone (e.g., many mosses, liverworts, lichens, and algae) or in the tropics (e.g., many ferns, cacti, orchids, andbromeliads). Many houseplants are epiphyte species due to their minimal water and soil requirements. Epiphytes provide a rich and diverse habitat for other organisms including animals, fungi, bacteria, and myxomycetes.Epiphyte is one of the subdivisions of the Raunkiær system.An epiphytic bromeliadThe term epiphytic derives from the Greek epi- (meaning 'upon') and phyton (meaning 'plant'). Epiphytic plants are sometimes called "air plants" because they do not root in soil. However, there are many aquatic species of algae, including seaweeds, that are epiphytes on other aquatic plants (seaweeds or aquatic angiosperms).