Byssocorticium atrovirens

A corticioid fungus growing strictly resupinate on decayed wood of broadleaved trees.

Recognized by its striking bright blue coloration, which can shift towards greyish-blue or greenish-blue, and its soft byssoid-cottony texture.

It may be confused with Byssocorticium pulchrum, which has slightly larger spores, and bears a strong superficial resemblance to Amaurodon viridis, which is differentiated by its distinctly verrucose spores.

Studied on two occasions in Orduña (Bizkaia), on dead wood of Quercus ilex and Fagus sylvatica, growing on the undersides of logs in December and February.