Summary:
Features include 1) resupinate growth on wood, 2) a fruitbody that is whitish, somewhat waxy, and firmly attached, with spines about 0.15cm long, the margin finely fibrillose to fringed, sometimes forming runners or rhizomorphs, 3) spores that are elliptic to short-cylindric, smooth, and colorless, 4) cystidia arising from the trama, projecting, evenly distributed over the spine, encrusted, cylindric to somewhat fusiform in distal part, 5) a dimitic hyphal system, the hyphae with clamp connections.

Microscopic:
SPORES 4.5-5.4 x 1.8-2.7 microns, elliptic to somewhat elongate, adaxially flattened, smooth, colorless, with small oblique apiculus; BASIDIA 4-spored, 18-22 x 4.5-6 microns, clavate, with basal clamp connection, sterigmata 2.7-3.6 microns long; CYSTIDIA 3.5-8 microns wide, "of tramal origin, evenly distributed over length of spine, numerous to abundant", more or less projecting, encrusted, cylindric to somewhat fusiform in distal part, with obtuse or more acute tip; HYPHAE dimitic, CONTEXT consisting of generative and skeletal hyphae, generative hyphae up to 5.4 microns wide, not inflating, branched, thin-walled to moderately thick-walled, septate with clamp connections, skeletal hyphae 2.7-5.4 microns wide, thick-walled to solid, context of spines similar, skeletal hyphae usually somewhat narrower, (Maas Geesteranus), SPORES 4-4.5 x 2-2.5 microns, short-cylindric, smooth, colorless; BASIDIA 4-spored, 4-5 microns wide, clavate; CYSTIDIA 6-8 microns wide, completely imbedded or projecting up to 30 microns, "abundant, sometimes projecting in clusters, scattered along sides of teeth and at apices", thick-walled, heavily encrusted; SUBICULAR HYPHAE closely interwoven, of 2 types: 1) 3-3.5 microns wide, "thin-walled, often branched, with frequent clamp connections", 2) 3-4 microns wide, thick-walled, aseptate, often encrusted, rarely branched, apparently ending in encrusted cystidia, (Gilbertson), SPORES 3.5-5 x 2-2.5 microns, (Martin)

Notes:
Steccherinum ciliolatum has been found in BC, AB, NB, ON, PE, PQ, AZ, CO, IA, MA, MD, MI, MN, MT, NC, NM, NY, and SC, (Ginns), as well as Europe (Maas Geesteranus).

Synonyms and Alternate Names:
Peniophora cretacea Bourdot & Galzin
Peniophora romellii Litsch. in Bourdot