Collybiopsis confluens,[4] commonly known as the clustered toughshank, is a type of mushroom from the Omphalotaceae family.

In early stages, they are whiteish and later turn from a cream to leather-yellow or pink-brownish colour.

The stem can be up to 10 cm (3.9 in) long, stiff, hollow, smooth and grooved along its length.

The thin, tough flesh is cream-brownish and gives off a weak, aromatic mushroom scent.

The skin of the cap (Pileipellis) is only slightly differentiated and consists of crawling, branched, and radially orientated hyphen.

[5][7] Amateurs would find it easy to confuse Collybiopsis confluens with other types of mushrooms.

The fruiting body appears from July to November mostly in rows of clusters or fairy circles from 1 to 5 meters in diameter.

As a substrate, deciduous and coniferous trees serve very well, however they grow most frequently on copper beech wood.

In the Holoartic realm, the distribution area reaches from the meridian to the subarctic climate zone.

In western Europe they can be found in France, Great Britain, in the Benelux countries and northwards to the Hebrides.

In 1828, Elias Magnus Fries gave the mushroom the name Maramius archyropus and so put it in the genus Marasmius.

[13] For a long time, the species was labelled as Collybia confluens, following Paul Kummer.