Crested tongue fern (Pyrrosia lingua f. cristata) belongs to the Polypodiaceae family. It is an evergreen fern that is a form of "Tongue fern", distributed westward from Kanto district of Honshu to Shikoku, Kyushu of Japan, as well as widely in the eastern Asia. This fern grows on rocky areas in the mountains, under trees, and on tree trunks. This form has a shape in which the tips of the leaves are separated due to abnormal growth points. It has been used as a garden plant since the Edo period.