Summary: Sistotrema farinaceum is a member of the Sistotrema brinkmannii group, described as follows, "Fruitbodies effuse, smooth or grandinioid; hyphae with clamps, walls hyaline; gloeocystidia absent; basidia urniform, normally with 6-8 sterigmata; spores less than 9 microns long, ellipsoid, subcylindrical, suballantoid, or subglobose, uninucleate (except for S. binucleosporum)", (Hallenberg, Latin name underlined). It is "distinguished by the farinaceous fruitbody with abundant crystals and the small basidia and spores" (Hallenberg).
Microscopic: SPORES 2.5-3.5 x 2.3-2.5 microns, nearly round, smooth, thin-walled; BASIDIA 6-8-spored, 8-9.5 x 3-4 microns, urniform to ovate, with basal clamp connection, true hymenium lacking: "basidia scattered in clusters on basal hyphae between abundant crystalline material"; whitish color and farinaceous appearance of the fruitbody caused by abundant crystal material; HYPHAE monomitic, with clamp connections, slightly ampullate, 2-3.3 microns wide, thin-walled, (Hallenberg)