Summary:
Features include 1) resupinate growth on all kinds of debris and decayed wood, as well as soil, humus, parts of living mosses, etc., in spring, 2) fruitbodies that are light red and granular, the margin mostly fibrillose with thin radiating rhizomorphs, 3) spores that are elliptic to ovoid, smooth, and inamyloid, 4) basidia that develop beneath a surface consisting of a dense layer of richly branching hyphidia and later project from the surface, and 5) a monomitic hyphal system, the hyphae with clamp connections.

Microscopic:
SPORES 6-10 x 4-5 microns, elliptic or somewhat ovoid, smooth, inamyloid, thin-walled, spore print light red; subhymenium thickening, composed of thin-walled hyphae, dendrohyphidia, and basidia at different stages of development; BASIDIA at first as probasidial bladders 10-20 x 5-10 microns, "of varying shape, ovoid, angular or prolonged, formed in the autumn and hibernating until April-June, when they develop a tubelike metabasidial part, penetrating to the surface where they project and form 4 sterigmata", length of basidia generally 40-60 microns (but depending on position of initial bladder), apical width 5-6 microns; DENDROHYPHIDIA numerous, forming a dense layer on surface of fruitbody, richly branched, thin-walled, the branches 0.5-1.0 microns thick, when old encrusted with small, granular crystals; CYSTIDIA none; HYPHAE monomitic at first white, then light rose, thin-walled, 2.5-4 microns wide, with clamp connections, subiculum formed by mostly horizontal, loosely interwoven, somewhat thin-walled hyphae, hyphae of rhizomorphs "parallel, often joined by anastomoses", (Eriksson)

Notes:
It has been found in in BC, AB, YT, Estonia, Finland, Norway, Sweden, (Eriksson).

Synonyms and Alternate Names:
Acanthophysium aurantium (Pers.: Fr.) G. Cunn.
Corticium aurantium Pers.