Red-tinged Lepiota
Leucoagaricus rubrotinctus
Also called ruddy dapperling, lepiota rubrotincta, red-tinged parasol
A slim, neatly built parasol whose reddish cuticle splits outward from a dark reddish-brown centre into fine coppery streaks over a white cap. The stem is smooth, white and hollow with a thin movable ring.
Overview
Leucoagaricus rubrotinctus, long known as Lepiota rubrotincta, is among the most elegant of the small North American parasols. Its cap is not scaly in the usual sense: instead of breaking into discrete patches, the reddish cuticle splits into fine radial fibres that stream outward from the dark disc like brushstrokes over a white ground, becoming sparser toward the margin.
The genus Leucoagaricus, within the Agaricaceae, contains lepiotoid fungi with free gills, white spore prints and movable membranous rings, distinguished from Lepiota proper by details of the cap cuticle and spore structure. This species is a typical representative, with a hollow stem, a thin ring and a clean, unchanging white flesh.
It is a summer fungus of warm, humid weather, appearing on litter and mulch in woodland, parks and gardens. Because it fruits when few other parasols are out and its colouring is so distinctive, it is one of the easier members of a difficult group to recognise in the field.
How to identify it
Cap
3-8 cm across, egg-shaped or bluntly conical at first, then expanding to convex and finally nearly flat with a low umbo. The disc is a solid reddish-brown to rose-red patch of intact cuticle; radiating from it, the cuticle splits into fine coppery-red to pinkish-brown fibres and streaks over a white to cream ground, so the cap appears finely rayed rather than scaly. The margin is thin, sometimes slightly striate, and may crack in dry conditions.
Gills
Free from the stem and separated by a narrow collar, crowded, moderately broad, white and remaining white or barely creamy in age. They do not bruise strongly, at most showing a faint yellowish or brownish edge where damaged.
Stipe
4-9 cm tall and 4-10 mm thick, slender, hollow, smooth and white to slightly pinkish-buff, tapering upward from a somewhat swollen or clubbed base. A thin white membranous ring hangs in the upper half and becomes movable on the stem once mature; it is delicate and can be lost in wet weather.
Flesh & spore print
Flesh thin and white, unchanging when cut, without reddening or yellowing. The spore print is white, and the spores are smooth, thick-walled ellipsoids with a germ pore, dextrinoid in iodine.
Where and when it grows
The Red-tinged Lepiota grows on rich humus, leaf litter and woody debris. Typical situations include the floors of hardwood and mixed woods, wooded parkland, shrub borders, mulched garden beds and wood-chipped paths. It fruits singly, scattered or in small loose groups, often along the edges of paths and in the shade of shrubs where the litter stays damp.
It is common in eastern North America, with a comparable population in California and reports from the Pacific Northwest, and similar material has been noted in Mexico and the Caribbean. Fruiting concentrates in warm humid weather from early summer into early autumn, and mulched landscaping tends to extend both its season and its range.
Ecological role
This species is a saprotroph feeding on dead plant material - fallen leaves, twigs, bark fragments and wood chips. Its mycelium spreads through the litter layer and upper soil, breaking down cellulose and lignin and converting the debris into humus, so it thrives wherever organic matter accumulates rather than where tree roots are dense.
Because landscaping mulch is essentially concentrated litter, this fungus has become considerably more common in urban and suburban settings than in undisturbed forest, and the same bed may fruit repeatedly through a wet summer. The thin, quickly maturing fruiting body is suited to short humid windows, expanding, printing its white spores and collapsing within a few days.
Similar species
Leucoagaricus americanus is larger and coarser, with flat brown concentric scales rather than radial fibres, a spindle-swollen stem, and flesh that turns wine-red when cut. Lepiota cristata is far smaller, with sparse flat reddish-brown scales in neat concentric rings and a slighter, more fragile build.
Leucoagaricus leucothites is comparable in size but entirely white with a smooth silky cap and no reddish tones, and its gills take on a pinkish tinge before ageing. Chlorophyllum molybdites is much bulkier, grows in lawns and drops a green spore print, while Amanita species of the same woods have a volva or bulb tissue at the stem base and gills attached differently, features absent here.