[GS] Pileus 2-4 mm. diam., olive grey with white striations at margin, hemispherical, smooth; flesh thin, olive grey, fragile. Gills adnexed, white to grey, ; moderately distant. Stipe 20-25 x 0-5-1 mm., white, translucent, solid, with narrow white disc at base. Spores 8-10 x 4-5um amyloid. Hymenophoral trama and tissue of pileus pseudo-amyloid. Dermatocystidia 20 x 8um, finely ornamented. Gill edge gelatinized and with cheilocystidia (Fig. 2/40, p. 37). HABITAT: on litter, Woodhaugh, Dunedin, 5.6.1953, Stevenson (type). [Desjardin] Basidiospores (Fig. 127) 7.4-8 x 4.2-4.8 um, smooth, hyaline, amyloid, thin-walled.- Basidia 4-spored.- Lamellar edge gelatinized; material too scanty and reviving poorly for analysis of hymenial cystidia, only a few collapsed cheilocystidia seen, these irregularly cylindric to clavate, with few, irregular, large apical excrescences.- Pileipellis a cutis of repent, densely diverticulate hyphae embedded in a gelatinous matrix; hyphae 1.5-3.5 umm diam, hyaline, inamyloid, thin-walled; diverticula simple or branched, 1.5-7 x 1-1.5 um; no acanthocysts nor cherocytes observed. Hypodermium of dextrinoid, hyphae inflated up to 20 mm diam, hyaline, non-gelatinous; with scattered oleiferous hyphae in pileus trama - Stipe tissue monomitic; cortical and medullary hyphae undifferentiated, smooth, hyaline, strongly dextrinoid, non-gelatinous- Caulocystidia from stipe apex short-cylindric or irregularly clavate, smooth; caulocystidia from stipe base (Fig. 128) and cystidia from basal ring irregularly cylindric, with the base of the cell knobby or with broad diverticula, and apex of cell with one to several long, filamentous, 'spidery' appendages, these smooth or with few diverticula, hyaline, inamyloid. Stevenson (1965) included M. subdebilis in sect. Sacchariferae without any explanation as to its placement. She described the pileus as smooth and the lamellar edges as gelatinized. The species clearly does not belong in sect. Sacchariferae because of a pileipellis of densely diverticulate hyphae embedded in a gelatinous matrix and lacking acanthocysts, a gelatinized lamellar edge, and caulocystidia with filamentous appendages. Mycena subdebilis is possibly allied with species in sect. Fragilipedes, although the caulocystidia of M. subdebilis are unusual for this section. [JAC] in GS paper the figure for the spore/cystidium says dermatocystdium, but main text implies cheilocystidium. Pileal surface with fine diverticulae. Partially gelatinised. Hypodermium of relatively small cells. Pseudoamyloid. Desjardin's caulocystidia not found. Has bunches of thin coiled diverticulae. 4-spored. length=6.7–8.1µm (µ=7.5, σ=0.31), width=3.4–4.5µm (µ=3.9, σ=0.26), Q=1.5–2.2µm (µ=1.90, σ=0.15), n=20. This is the same as M. 'Perseverence Rd'.

[Notes from Kew Type specimen, PRJ 2010] Kew images.

On litter under broad-leaved trees in forest, Otari, Wellington, 3.4.1961, L. R. & G. M. Taylor.

Pileus 2-4 mm diam., olive grey with white striations at margin, hemispherical, smooth; flesh thin, olive grey, fragile. Gills adnexed, white to grey, moderately distant. Stipe 20-25 x 0.5-1 mm, white, translucent, solid, with narrow white disc at base. Spores 8- 10 x 4-5 µm amyloid. Hymenophoral trama and tissue of pileus pseudo-amyloid. Dermatocystidia 20 x 8 µm, finely ornamented. Gill edge gelatinized and with cheilocystidia (Fig. 40).

On litter, Woodhaugh, Dunedin, 5.6.1953, Stevenson (type).

Pileus 2-4 mm diam., olivaceo-griseus, margine albo-striatus, hemisphaericus, laevis; caro tenuis, olivaceo-grisea, fragilis. Lamellae adnexae, albae usque griseae, modice distantes.  Stipe 20-25 x 0.5-1 mm, albus, translucens, solidus, basi disco angusto albo praeditus. Sporae 8-10 x 4-5 µm, amyloideae. Trama hymenophoralis et pilei textura pseudo-amyloidea. Dermatocystidia 20 x 8 µm, tenuiter ornata. Lamellarum acies gelatinosa, cheilocystidiis instructa.

Typus: Stevenson 915.