Pluteus umbrosus

Description

Pluteus umbrosus is a species of Fungi in the family Pluteaceae. The cap is 4 to 9 cm in diameter and is sepia to dark brown, usually with slightly darker radial streaks, being convex at first and then flattened, with a wrinkled fibrous surface giving a velvety appearance. It is a fairly rare late summer and autumn fungus that grows on the rotting wood debris of deciduous trees. The radially wrinkled cap and pale pink gills are distinctive.

This species is found throughout much of northern and central mainland Europe, and it is also recorded in North America.

Common names: Velvet Shield.

Mushroom Identification

1. Cap

   3 to 9 cm in diameter, the cap is sepia to mid-brown, darkest towards the center, usually with slightly darker irregularly radial marks. Convex at first and then almost flattened, with a radially wrinkled fibrous surface. Beneath the cuticle, the cap flesh is white and firm.

2. Stem

   The stem is 3 to 8cm long and 5 to 12mm in diameter of more or less constant diameter or very slightly bulbous at the base. Its background color is white to pale fawn, covered in small brown soft scales.

3. Gills

   Are white at first, becoming pale pink with distinctive dark brown edges, the gills are broad, crowded, and free of the stem.

4. Spores

   Subglobose, 6-7 x 4-5µm.

5. Spore Print

   Pale pink.

6. Odor and Taste

   Are not distinctive.

7. Habitat

   Solitary or in small groups on stumps, rotting fallen branches, and other woody debris of broadleaf trees; very occasionally on conifer stumps. This species also appears on sawdust heaps.

Look-Alikes

1. Pluteus cervinus

   Differs in the color of the edge of the plates, the absence of a mesh pattern on the cap, and the structure of the cystids.

2. Plyuteus atromarginatus

   Differs in the structure of pleurocystids, and grows in coniferous forests.

3. Pluteus punctipes

   Is noted as the closest species, it differs in the surface of the cap and the color of the edge of the plates.

History

This wood-rotting mushroom was described scientifically in 1798 by South African mycologist Christiaan Hendrik Persoon, who gave it the name Agaricus umbrosus. (In the early years of fungal taxonomy most gilled fungi were initially placed in a giant Agaricus genus, most of the contents of which have now been redistributed to many other genera.)

It was the celebrated German mycologist Paul Kummer who, in 1871, transferred this species to the genus Pluteus, thereby establishing its currently-accepted scientific name Pluteus umbrosus.

Pluteus, the genus name, comes from Latin and means a protective fence or screen - a shield for example.

The specific epithet umbrosus comes from Old Latin umbra, meaning a shadow - a reference to the darkly shaded area in the center of the cap of this shield mushroom.

Synonyms

1. Pluteus cervinus var. umbrosus (Pers.) J.E. Lange 1938

2. Agaricus umbrosus Pers. 1798

Photo sources:

Photo 1 - Author: MK-fotky (Attribution-NonCommercial-NoDerivs 2.0 Generic)

Photo 2 - Author: MK-fotky (Attribution-NonCommercial-NoDerivs 2.0 Generic)

Photo 3 - Author: MK-fotky (Attribution-NonCommercial-NoDerivs 2.0 Generic)

Photo 4 - Author: nz_willowherb (Attribution-NonCommercial 2.0 Generic)