Sadleria cyatheoides, commonly known as ****amaumau fern or amau, is a fern species in the family Blechnaceae, in the eupolypods II clade of the order Polypodiales, in the class Polypodiopsida. It is endemic to Hawaii and inhabits lava flows, open areas, and wet forests on all major islands up to an altitude of 1676 m. Reaching a height of 0.9 - 1.5 m and a trunk diameter of 7.5 - 10 cm, amau resembles a small tree fern. Kīlauea's Halemaʻumaʻu is named for this species. Its pith and young fronds are edible either roasted or steamed.

Description

The young fronds are often tinged red to block harmful rays from the Sun.