The whiteworm lichen (Thamnolia vermicularis) belongs to the family Icmadophilaceae. This lichen grows on the ground in the alpine zone, and the thallus is erect or decumbent, up to 12 cm in height. The thallus is white and tubular, usually 1-2 mm wide, slightly bent to form a roundworm, and has a sharp tip. It has commonly been used as a tea with the local name of "snow tea" in some parts of China. It has been believed to counteract inflammation and has been used in traditional Chinese medicine over long periods of time.