Lepiota subincarnata Identification Guide

First impression

Lepiota subincarnata, long known also as L. josserandii, is a small dapperling with a distinctly warm, pinkish personality. Caps run 2 to 4 cm across, and at arm's length they look soft, felted and flesh-pink with a slightly deeper centre rather than obviously scaly. Only when you crouch and use a lens does the covering resolve into hundreds of small, neat squamules.

Fruit bodies typically come in small gregarious troops, sometimes with two or three joined at the base, standing in leaf litter, mulch or bark chippings. They are slender, tidy things, easy to overlook among the general pink-buff clutter of an autumn border.

The setting

Search rich humus and organic mulch. The most productive sites are wood-chip and bark beds, garden borders, shrubberies in parks, hedgerows, path edges under planted trees, and damp deciduous woodland on calcareous soil under beech, hazel and oak. It is a saprotroph of well-rotted plant material, which is why fresh mulch spreads it so effectively through gardens and amenity plantings.

Season runs from summer through late autumn. Where mulch is regularly topped up, colonies can appear year after year in exactly the same bed.

Step one: read the cap

Shape. Hemispherical when young, then convex, and finally flattened with a broad, low umbo. Old caps may become slightly depressed around the umbo.

Ground colour. Pale pinkish-cream to flesh-pink, sometimes almost whitish at the extreme margin.

Covering. The cuticle breaks into fine, small, appressed squamules of a slightly deeper pinkish-brown, reddish-brown or soft brick tone. They are densest at the centre, where they merge into a solid, more uniformly coloured disc, and they thin outward. Critically, they do not organise into sharply defined concentric belts; the distribution is comparatively even, which is why the overall effect reads as felted rather than target-patterned. Assess this from directly above on a dry cap.

Margin. Even, occasionally carrying tiny pale fibrillose flecks left by the veil, and not striate.

Step two: read the gills

Section the cap vertically. The gills are free, with a visible gap between their inner ends and the stem apex. They are crowded, moderately broad, and white to pale cream, sometimes acquiring a faint pinkish tinge in age from reflected cap colour rather than from spore deposit. Under a lens the gill edge is even and finely floccose.

Free, pale, crowded gills under a small squamulose cap is the classic Lepiota architecture, and confirming it in section is more reliable than squinting at the underside in the field.

Step three: read the stem

The stem is 2 to 4 cm long and 3 to 7 mm thick, cylindrical, frequently curved where it has pushed through mulch, and slightly enlarged at the base. It separates cleanly from the cap.

Above the veil zone it is whitish and silky. Below it, the surface is covered with pale pinkish-brown fibrils, often gathered into one or two woolly, girdle-like bands. The ring itself is thin and cottony and is frequently gone entirely by maturity, leaving only a boundary where the smooth white upper stem meets the fibrillose pinkish lower stem. There is no thick, movable, double ring.

When you extract a specimen, lift it with the surrounding mulch. The stem base is often bound into a mat of white mycelium that runs through the chippings, and that mycelial mat is a useful record of the substrate.

Step four: flesh, colour change and odour

Split the fruit body lengthways. The flesh is thin and white in the cap, becoming pale pinkish in the stem and most obviously so at the base, either already present or developing slowly at the cut. There is no bluing, no greening, no yellowing and no latex.

The odour is faint and slightly sweetish or weakly aromatic. It is emphatically not the sharp, penetrating, rubbery smell that identifies Lepiota cristata, and that negative is a genuinely useful field character when the two grow near one another.

Step five: the spore print

Set a mature cap gills-down on card that is half black and half white, cover it, and leave it overnight. The deposit is white to cream.

Under a microscope, the spores are small, roughly 5.5 to 8 by 3 to 4.5 micrometres, ellipsoid, smooth, without a projecting spur, and dextrinoid, turning red-brown in Melzer's reagent. Cheilocystidia on the gill edge are clavate to narrowly clavate. The cap covering is a trichoderm of long cylindrical elements, which is what produces the fine even squamules you saw with the lens. The combination of small, unspurred, dextrinoid spores with a pinkish squamulose cap and a girdled stem is what places the species.

Separating it from the look-alikes on morphology

Lepiota brunneoincarnata is the nearest relative. It has coarser, darker scales in a dark vinaceous- to greyish-brown, arranged in crisper concentric zones on a paler cream ground, giving a target-like cap. It is also typically a species of short mown turf, verges and lawns rather than mulch and woodland humus. Where habitat overlaps, judge the tone and coarseness of the cap covering.

Lepiota cristata has rusty reddish-brown scales on a clean white ground, concentrated centrally and often in a more broken pattern, a small but genuinely membranous white ring on an otherwise smooth stem, a strong pungent odour, and characteristically spurred, triangular spores.

Lepiota castanea is darker, with chestnut to reddish-brown squamules arranged in more regular radiating rows, and its spores are elongate and spurred.

Lepiota clypeolaria is larger and more slender with an ochre cap and a conspicuously shaggy, woolly stem, a completely different stem texture.

Cystolepiota species such as C. seminuda are tiny, with a mealy, powdery, easily smudged cap covering rather than defined squamules, and some carry lilac or yellow tints.

Leucoagaricus species are generally larger, with a well-formed persistent ring and either smooth or coarsely fibrillose caps, and several show strong reddening in the flesh.

Young Agaricus species are ruled out by their gills, which pass from pink to chocolate-brown, and by their brown spore print.

Melanophyllum species have greenish or reddish gills and a coloured spore print.

A working field sequence

1. Note the substrate: mulch, bark chips, rich humus or calcareous woodland litter.
2. Measure the cap; 2 to 4 cm and flattening with a broad low umbo.
3. Use a lens on the cap: fine, evenly distributed pinkish-brown squamules, not sharp concentric zones.
4. Section the cap and confirm free, crowded, white to cream gills.
5. Check the stem for pinkish-brown fibrillose girdles and a fleeting cottony ring zone.
6. Split the stem and look for a pinkish flush toward the base.
7. Take a spore print and expect white to cream.