Antrodia xantha

Antrodia xantha (yellow antrodia) is a small, crust-forming polypore in the family Fomitopsidaceae. Rather than producing a stalked mushroom, it spreads as a thin, bright yellow resupinate layer over dead conifer wood, with a poroid lower surface and a tough, corky texture. It is a brown-rot (wet rot) fungus and is not edible; it has no established culinary or medicinal use.

History

Antrodia xantha is recognised mycologically as a wood-decay fungus rather than a foraged or cultivated species. It is repeatedly listed among the wet rot fungi that damage timber in buildings, alongside Serpula lacrymans, Coniophora puteana and Antrodia vaillantii. It should not be confused with Antrodia cinnamomea (Taiwanofungus camphoratus), the prized Taiwanese medicinal fungus; claims of liver-supporting, antioxidant or anti-inflammatory benefits in older sources belong to that unrelated species, not to A. xantha.

Overview

Ecologically, Antrodia xantha acts as a decomposer of dead and worked conifer wood, contributing to nutrient cycling in forests but also figuring among the fungi responsible for structural wood decay. Its key field characters are the absence of a cap or stem, the bright yellow resupinate fruit body, and the small angular pores on the underside. There is no reliable evidence that it is edible, and it has no recognised value as a culinary or medicinal mushroom.