Snowy Waxcap
Cuphophyllus virgineus
Also called virgin waxcap, ivory waxcap, snowy wax cap
A small, slender, entirely white waxcap with thick decurrent gills and a tapering stem, often the last waxcap still fruiting in the turf after the first frosts.
Overview
The Snowy Waxcap is one of the most abundant and most persistent waxcaps of autumn grassland. It is pure white to faintly ivory throughout, small and slender, and appears in troops scattered through short turf, often continuing to fruit into December when the brighter species have finished. In wet weather the cap becomes translucent and slightly greasy, showing the lines of the gills through the flesh.
Like the Meadow Waxcap it belongs to Cuphophyllus, the group of waxcaps with decurrent gills, dry to sub-viscid caps and muted colours, separated from Hygrocybe on molecular and anatomical grounds. Older literature uses Hygrocybe virginea or Camarophyllus niveus, and several closely related varieties and forms are recognised within the complex.
Its pale simplicity is deceptive: the thick, waxy, widely spaced, strongly decurrent gills mark it unmistakably as a waxcap rather than one of the many small white grassland agarics with thin crowded gills.
How to identify it
Cap
1–5 cm across, convex then flattening and often becoming slightly depressed or wavy-margined, occasionally with a low umbo. The surface is white to ivory or faintly cream, sometimes with a pale ochre flush at the centre in age, smooth and slightly greasy when wet, drying matt and silky. Wet caps are hygrophanous and translucently striate at the margin.
Gills
Thick, soft, waxy, distinctly distant and strongly decurrent, running well down the stem. They are white to ivory, sometimes faintly interveined at the stem apex, and their broad waxy texture is obvious if a gill is rubbed between finger and thumb.
Stipe
Slender, 2–7 cm tall and 3–8 mm thick, white, smooth, dry, often slightly curved or flattened and typically tapering downwards to a narrow base. It becomes hollow with age and bears neither ring nor volva.
Flesh and spore print
The flesh is thin, white, soft and unchanging when cut. The spore print is white and the spores are smooth and ellipsoid. A related form, sometimes treated as var. fuscescens, develops brownish discoloration on the cap and stem with age, but the typical form stays clean white.
Where and when it grows
A grassland fungus of short, closed turf: churchyards, cemetery lawns, old pastures, mown grass on commons and campuses, upland grassland, dune slacks and coastal cliff tops. It is somewhat more tolerant of mowing and mild fertility than the rarest waxcaps, and is often the most numerous waxcap at a given site.
The season peaks from October onwards and can extend into December or January in mild winters, making it the last of the group to disappear. It is widespread and common across temperate Europe, and recorded from North America and other temperate regions; it commonly grows in troops, scattered lines or partial rings through the sward.
Ecological role
The Snowy Waxcap maintains a perennial soil mycelium in grassland rather than decaying wood or leaf litter. Grassland waxcaps as a group are now thought to be biotrophic, drawing carbon through associations with grassland plants or bryophytes rather than living freely as saprotrophs, which explains their absence from compost, mulch and disturbed ground and their resistance to cultivation.
Fruiting is triggered by falling temperatures and autumn rain, and this species tolerates colder conditions than most of its relatives, extending the waxcap season well past the first frosts. Colonies can persist in the same patch of turf for many years, provided the ground is not ploughed, reseeded or fertilised.
Similar species
Cuphophyllus pratensis is much larger and apricot-buff rather than white, though it shares the decurrent gills. Cuphophyllus russocoriaceus is virtually identical in shape and colour but is smaller, often with a faint yellowish tint at the stem base, and has a distinctive cedarwood or sandalwood odour. Pale forms of Hygrocybe such as H. ceracea have adnate to slightly decurrent gills and a yellow tone.
Among non-waxcaps, small white Clitocybe species look superficially similar but have thin, crowded, non-waxy gills and a firmer, less translucent cap; Marasmius oreades has a tan cap, free to adnexed gills and a tough pliant stem. Any small white grassland mushroom with thick, well-separated, waxy gills running down the stem is almost certainly this species or a close relative.