Tongue fern, scientifically known as Pyrrosia lingua, is a species of fern that usually grows on rocky slopes, cliffs, or ridges. While the name "tongue fern" originated from the shape of its fronds that resemble a tongue, there are several other synonyms used to describe this plant. Some of these synonyms include common bladder fern, strap fern, and rock fern. Local names for the plant include the Chinese gold-dust fern, Korean gold-dust fern, and jinmailang in Chinese. Regardless of the synonym used, the plant is known for its delicate and unique fronds and is often used for decorative purposes.