Asplenium antiquum

Asplenium antiquum is a fern of the family Aspleniaceae, commonly known as bird's-nest ferns (also called spleenworts). In Japanese, it is known by ō-tani-watari and tani-watari. It grows on cliffs, logs and rocks, near waterfalls, in damp forests, and on tree trunks in China, Japan, Korea, and Taiwan. It is classified as an endangered species in both South Korea and Japan.