Summary:
Sistotrema porulosum 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). Sistotrema porulosum is characterized by a thin, adnate, gray, porulose fruitbody, (and by the pluri-nucleate SS-mycelia in culture).

Microscopic:
SPORES 3.5-4.5 x 2-2.5 microns, elliptic, smooth, thin-walled; BASIDIA (4)6-8-spored, 10-20 x 3.5-4.5 microns, urniform; with basal clamp connection; HYPHAE monomitic, with clamp connections, sometimes ampullate, with an oily content, 2-4.5 microns wide; SUBICULUM very thin and with rather sparsely septate hyphae, running parallel to substrate, with thickened walls, (Hallenberg)

Notes:
Sistotrema porulosum has been found in BC, ON, and PQ, (Hallenberg).

Synonyms and Alternate Names:
Aleurodiscus amylaceus (Bourdot & Galzin) D.P. Rogers & H.S.
Corticium amylaceum Bourdot & Galzin