Mycena olivaceomarginata Massee syn. M. avenacea (Fr.) Quél. Gras-Helmling Brownedge Bonnet. Cap 1–2.5cm across, convex to bell-shaped, olive-brown with lined or grooved margin. Stem 50–70 x 2–3mm, concolorous with cap, lighter at apex, covered in fine white down at base. Flesh very thin, white to brown. Taste mild, smell radishy. Gills adnate, whitish with darker yellowish-brown or olive edge. Cheilocystidia comprising a mixture of thin-walled fusoid elements and more or less club-shaped bodies, the apex covered in short to elongate filiform processes. Spore print cream. Spores ellipsoid, amyloid, 9–12 x 5–6um. Habitat on unimproved lawns or short grassland. Season autumn. Abundant. Not edible. Found In Europe.