The species has cystidia that do not possess individual crystal protrusions but are instead smooth or only slightly rough and basidiospores that are fusiform and moderately large, 8.1–10.9 × 2.7–3.3 µm.

PUERTO RICO. Municipio Rio Grande, Luquillo Mts, El Yunque, Mount Britton Trail, between upper road and trail head, 760-880 m, 18.3003, -65.7917, on wet dead wood, 11 Jun 1998, K.-H.Larsson (KHL 10444 in GB).

inornatum (Lat.), without ornament, referring to the almost smooth cystidia.

Basidiomata annual, effused, resupinate, soft and fragile, arachnoid, thin, loosely adnate. Hymenophore smooth, finely velutinous due to numerous protruding cystidia, whitish. Margin thinning out, adnate.

system monomitic. All septa with clamps. Subiculum thin, with loosely interwoven richly branched hyphae 3–4 µm wide, hyaline, thin-walled to slightly thick-walled, covered by a thin hyaline crystal sheath giving them a slightly rough appearance. Subhymenial hyphae similar to those in subiculum, but more compactly arranged and slightly agglutinated. Cystidia subulate, 45–60 × 4–5.5 µm including encrustation, projecting up to 45 µm, occasionally with slight basal swelling (up to 6 µm), terminal, thick-walled and with an outer hyaline crystal sheath covering the whole cystidium except the thin-walled acuminate apex. Surface of the crystal sheath slightly rough, crystal protrusions lacking.

Basidia suburniform to almost clavate, 10–14 × 4.5–6 µm, thin-walled, with 4 sterigmata and a basal clamp, often with hyaline crystalline collar at the base. Basidiospores fusiform, L=(7.2)8.1–10.9(–11.0) µm, W=(2.5–)2.7–3.3(–3.5) µm, Q=(2.4–)2.7–3.8(–4.1), N=97/1, with minute apiculus, smooth, thin-walled, hyaline, negative in Melzer’s reagent.

COSTA RICA. Puntarenas: Carrara Biologica Reserva, ca. 50 m, 9.7472, -84.6278, on dead fruit-bodies of Coriolopsis rigida (Berk. & Mont.) Murill, 14 Jun 1991, L.Ryvarden (LR 29823 in O:F 506780). PUERTO RICO. Municipio Cayey, Bosque Estatal Carite, Guavate Picnic area, 18.1264, -66.0764, on dead wood, 23 Jun 1996, K.-H.Larsson (KHL 9289 and 9337 in GB).

This is the only species in which cystidia and hyphae have a similar surface, which is smooth or slightly rough due to a thin layer of crystalline matter.