Clustered Toughshank
Gymnopus confluens
Also called confluent clitocybe, tufted collybia
Crowded tufts of slim pale mushrooms whose long stems, densely coated in fine white hairs, fuse together at a common base buried in the leaf litter.
Overview
Gymnopus confluens, formerly Collybia confluens, is a leaf-litter agaric that fruits in unmistakably dense, crowded clumps. The specific epithet refers to the way many stems run together at a shared base, so that a whole handful of mushrooms lifts as a single unit.
The caps are thin and pale and vary greatly with moisture, but the stems are the giveaway: long, tough, and covered from top to bottom with a fine whitish pubescence that gives them a matt, frosted appearance quite unlike the polished stems of related species.
It is common through European and North American broadleaved woodland, often forming rings and arcs through the litter where the mycelium has expanded outward over many seasons.
How to identify it
Cap
The cap is 1-4 cm across, thin-fleshed, convex then flattened and often with a low broad umbo, pale pinkish buff to tan when moist and drying rapidly to cream or almost white. The margin is often slightly wavy or grooved in age.
Gills
Gills are exceptionally crowded and very narrow, whitish to pale pinkish buff, and are free or only narrowly attached to the stem.
Stipe
The stem is 5-9 cm long and 2-4 mm thick, tough, hollow, often flattened or grooved, reddish brown beneath a dense coat of fine white hairs that make it look grey or frosted. Stems are fused at the base into a common tufted mass with white mycelium binding the surrounding leaves.
Flesh and spore print
Flesh is thin, whitish and pliant. The spore print is white.
Where and when it grows
The Clustered Toughshank grows in deep leaf litter of broadleaved woodland, particularly under beech and oak, and also occurs in conifer needle litter. It typically fruits in large dense tufts, and repeated fruiting from a spreading mycelium often produces long arcs or partial rings across the woodland floor.
The season runs from summer to late autumn, and the species is widespread throughout temperate Europe, Asia and North America.
Ecological role
This is a saprotroph of fallen leaves and fine litter. Its mycelium forms extensive sheets that glue leaves together and slowly bleach them as the cellulose is removed, and because the mycelium is long-lived it advances outward year on year, producing the characteristic arcs of fruit bodies.
The tufted habit concentrates many fruit bodies over a single well-colonised patch of litter, and the tough, hairy stems resist drying, letting a clump continue releasing spores over a comparatively long period.
Similar species
Gymnopus dryophilus has a smooth, bald, cartilaginous stem, a more russet cap and grows scattered or in loose troops rather than dense fused tufts. Gymnopus peronatus has hairs concentrated as a conspicuous woolly mass at the stem base only, with the rest of the stem nearly smooth, and its gills are much more widely spaced.
Gymnopus erythropus has a smooth, shining reddish stem. Marasmius wynneae also grows in beech litter but has a broader pale cap with lilac tints, far fewer and more distant gills, and a two-toned stem with a woolly base rather than an all-over frosted coating.