[GS]Pileus 1-3 cm. diam., fawn, plano-convex with a sharp umbo, grooved, margin waved, velvety. Gills adnate, moderately distant, whitish. Stipe 2-4 cm. x 2 mm., vinaceous grey darker towards base which is slightly swollen and to which rhizomorphs are attached, fibrillose striate, tough, hollow lined with white silky fibrils; flesh vinaceous. Spores 8-10 X 4-5um, nonamyloid, thin-walled (Fig. 2/23, p. 37); print white. Hymenophoral trama of hyphae 5um diam., with clamp connections. Cuticle of similar hyphae, weakly pseudo-amyloid, with palisade-like hyphal endings. HABITAT: on Photinia litter, grounds of Gawthorn Institute, Nelson, 26.4.1957, E. B. Kidson in Stevenson (type). [EH] This species was originally found in lawns under Photinia, an introduced rosaceous plant. We are inclined to consider C. kidsonii an introduced fungus as well. [JAC] the fruitbodies are clearly attached to wood, not leaf litter. The cap contains oleiferous hyphae. Spores length=8.4–11.6µm (µ=9.9, σ=0.79), width=4.1–5.3µm (µ=4.6, σ=0.33), Q=1.9–2.6µm (µ=2.14, σ=0.14), n=20. 4-spored hyphae clamped. This is a good Gymnopus and appears to be identical to G. subpruinosus, known from both native and exotic habitats in NZ.

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

Pileus 1-3 cm diam., fawn, plano-convex with a sharp umbo, grooved, margin waved, velvety. Gills adnate, moderately distant, whitish. Stipe 2-4 cm x 2 mm, vinaceous grey darker towards base which is slightly swollen and to which rhizomorphs are attached, fibrillose striate, tough, hollow lined with white silky fibrils; flesh vinaceous. Spores 8-10 x 4-5 µm nonamyloid, thin-walled; print white. Hymenophoral trama of hyphae 5 µm diam., with clamp connections. Cuticle of similar hyphae, weakly pseudo-amyloid, with palisade-like hyphal endings.

On Photinia litter, grounds of Cawthorn Institute, Nelson, 26.4.1957, E. B. Kidson in Stevenson (type).

Pileus 1-3 cm diam., hinnuleus, plano-convexus cum umbone acuto, sulcatus, margine undulatus, velutinus. Lamellae adnatae, modice distantes, albidae. Stipes 2-4 cm x 2 mm, vinaceo-griseus (basin versus fuscius), basi leviter tumida rhizomorphas gerente, fibrilloso-striatus, tenax, cavus, cavitate albo-sericeo-fibrillosa; came vinacea. Sporae 8-10 x 4-5 µm, haud amyloideae, parietibus tenuibus; in cumulo albae. Trama hymenophoralis ex hyphis fibulatis 5 µm diam. sistens. Cuticula ex hyphis similibus aegre pseudo-amyloideis sistens, terminationibus hyphalibus sepimentiformibus.

Typus: E. B. Kidson in Stevenson 1193.