Dermoloma cuneifolium

What You Should Know

Dermoloma cuneifolium is a species of fungus in the family Tricholomataceae, and the type species of the genus Dermoloma. Cap is initially conical or convex, later broadly convex or flattened, sometimes with a low umbo, or occasionally with a shallow depression; light brown to gray-brown; surface wrinkled radially; 1 to 6cm across when fully mature often cracking into irregular patches mainly concentrated towards the center. Gills brittle; pale grey; moderately distant, sinuate-adnate to emarginate. The stem is Whitish or pale grey, with fine longitudinal fibrils; cylindrical or slightly tapering towards base; 1.8 to 6.5cm long, 0.2 to 1cm diameter; no stem ring.

Other names: Crazed Cap.

Dermoloma cuneifolium Mushroom Identification

1. Ecology

   Possibly saprobic, since it is sometimes found in grasslands without trees nearby; growing gregariously in grassy areas or hardwood forests; summer and fall; common in Europe; North American distribution uncertain (reported primarily from the Midwest).

2. Cap

   3–5 cm across; at first, convex, becoming broadly convex to nearly flat; dry; bald; gray-brown, with a slightly darker center.

3. Gills

   Attached to the stem by a notch; close or nearly distant; short-gills frequent; white.

4. Stem

   3–5 cm long; 0.5–1 cm thick; equal; bald; dry; white.

5. Flesh

   White; unchanging when sliced.

6. Odor and Taste

   Mealy.

7. Spore Print

   White.

8. Microscopic Features

   Spores 4.5–7 x 2.5–4 µm; long-ellipsoid; smooth; hyaline in KOH; inamyloid. Lamellar trama parallel. Basidia 4-sterigmate. Hymenial cystidia not found. Pileipellis hymeniform; terminal elements pyriform, 10–25 µm across, smooth, hyaline in KOH. Clamp connections are present.

Dermoloma cuneifolium Look-Alikes

1. Dermoloma josserandii

   Appears in similar habitats; its gills are usually slightly decurrent and it has a more granular cap surface; its spores are amyloid.

2. Melanoleuca polioleuca

   Look rather like Dermoloma mushrooms but they do not usually have crazed caps and they also differ in having finely-warty spores rather than smooth spores.

Dermoloma cuneifolium Taxonomy and Etymology

When the great Swedish mycologist Elias Magnus Fries described this mushroom in 1818, he gave it the scientific name Agaricus cuneifolius. Its currently-accepted name Dermoloma cuneifolium dates from a 1986 publication by French mycologist Marcel Bon.

Synonyms of Dermoloma cuneifolium include Agaricus cinereorimosus Batsch, Agaricus atrocinereus Pers., Agaricus cuneifolius Fr., and Tricholoma cuneifolium (Fr.) P. Kumm.

Dermoloma cuneifolium is the type species of its sparsely-populated genus. Two varieties of this species have been recorded: the autonomous Dermoloma cuneifolium var. cuneifolium (Fr.) Bon, and the more recently described Dermoloma cuneifolium var. punctipes Arnolds.

Dermoloma, the genus name, comes from Derma- meaning a skin, and -loma meaning a fringe or hem. It is a reference to the way the pileipellis (the topmost layer of hyphae that make up the pileus or cap skin) of mushrooms in this group overhangs the margin of the cap.

The specific epithet cuneifolium means literally 'with leaves tapered to the base', and in the context of this particular mushroom, it refers to the way that the gills are stepped sharply so that they reduce in width towards the stem.

Sources:

Photo 1 - Author: Davide Puddu (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 2 - Author: Irene Andersson (irenea) (Creative Commons Attribution-Share Alike 3.0 Unported)