The oak leaf fern (Tectaria zeilanica) belongs to the family Tectariaceae. It is an evergreen fern that is native to southern China, Taiwan, Southeast Asia, India and Sri Lanka. This fern grows on muddy rocks in forests and near streams, and cn reach 10-20 cm in height. The fronds are obviously dimorphic. The sterile fronds are usually in rosette, not erect, shaped like small oak leaves. The fertile fronds are erect, stipe slender, 20-25 cm long. The sori are orbicular, anastomosing in line, and cover throughout abaxial surface when mature.