Such plants were therefore called "saprophytes". Clostridia are found extensively in nature predominantly as benign soil saprophytes. It is a plant parasite as well as saprophytes on both agricultural and forest trees. Some species of "Ascomycetes" form their structures within plant tissue, either as parasite or saprophytes. They are saprophytes and have small fruiting bodies. However, pathogens and saprophytes may also be endophytic at some point of their life cycle. Although "C. globosum" are saprophytes, they can cause opportunistic human onychomycosis and cutaneous infections. They are parasites or commensals of vertebrates, insects, or plants; some are saprophytes.