A small, very delicate, pure-white parasol mushroom with a strongly striate cap, free gills, and an extremely fragile ring. The cap is thin-fleshed, often chalky or finely powdery, and collapses easily. A widespread saprobe globally, and based on your collections, present in New Zealand, especially in native bush litter and wood-rich microhabitats.

Cap: 15-50 mm, convex to plano-convex, sometimes shallowly depressed. Colour pure white, occasionally with a faintly cream or greyish centre, but never brownish. Surface chalky, powdery, or finely granular, sometimes appearing frosted. Strongly translucent-striate, often halfway to the disc. Flesh very thin, fragile, white, unchanging.
Gills: Free, crowded, thin. White, remaining pale throughout development. Edges smooth.
Stipe: 40-90 x 2-5 mm, very slender, hollow, easily collapsing. White, smooth or faintly powdery. Ring extremely fragile, often disappearing early or absent in mature specimens. Base sometimes slightly swollen but not distinctly bulbous.