Tricholoma sciodes

Description

Tricholoma sciodes is a rare discovery beneath broad-leaf trees, typically occurring on calcareous soil. Its identification is aided by the presence of reddish or lilaceous tints; however, within the genus Tricholoma, there are several other similar-looking species with greyish caps, making confident differentiation challenging. It emerges during autumn, often appearing in small clusters beneath mature beech and oak trees. This species can also be found in numerous countries across mainland Europe.

Tricholoma sciodes is a poisonous toadstool and should never be collected for consumption. Additionally, there are other gray- and gray-brown species within this genus that are also toxic, making it risky to include any except the most distinctive 'knights' in mushroom dishes.

Common names: Beech Knight, German (Schärflicher Ritterling).

Mushroom Identification

1. Cap

   The caps of these mushrooms reach up to 4.72 inches (12 cm) in diameter at full maturity, displaying a gray coloration with darker shades towards the center and radial lines. Initially, they have a convex shape but flatten out as they grow, occasionally exhibiting a slight umbo.

2. Gills

   The gills are moderately spaced apart and have a sinuate appearance. They are white with small dark flecks along their edges.

3. Stem

   The stems are typically 0.39 to 0.79 inches (10 to 20 mm) in diameter and 1.57 to 3.15 inches (4 to 8 cm) long. They slightly broaden towards the base and are off-white in color. Longitudinal grey fibrils are present, particularly noticeable in the central region of the stem.

4. Spores

   The spores are ellipsoidal and smooth, measuring 6.5-7.5 x 5-6.5μm. They have a hilar appendage and are inamyloid.

5. Spore Print

   The spore print is white.

6. Odour and Taste

   They have a slightly earthy odor and a bitter taste.

7. Habitat

   These mushrooms form mycorrhizal associations and are commonly found in broad-leaf woodlands, particularly in the presence of beech trees and oaks. Their season typically spans from July to October.

Look-Alikes

1. Tricholoma portentosum

   Distinguished by having yellowish shades on the stem and, in any case, is always found under the cuticle.

2. Tricholoma terreum

   Similar in appearance but occurs mainly in coniferous woodland.

3. Tricholoma scalpturatum

   Has yellowing gills and cap edges, and its spores are much narrower.

4. Tricholoma virgatum

   Has a darker cuticle and grows under conifers.

5. Tricholoma bresadolanum

   Also grows under broad-leaved trees, but has a stem covered with shaggy greyish scales.

6. Tricholoma bresadolanum

   Distinguished from T. sciodes by its greater rarity, the shades of pink at the base of the stem, its greater robustness, and the presence of rather pronounced scales on the stem and pileus.

History

In 1801, Christiaan Hendrik Persoon provided a scientific description of this mushroom and named it Agaricus sciodes, establishing it as the basionym. During the early days of fungus taxonomy, the majority of gilled mushrooms were initially classified under the genus Agaricus. However, over time, most of them were reclassified into newer genera, leaving only the 'true mushroom' in the more manageable Agaricus genus.

In 1919, French naturalist Charles-Édouard Martin (1847-1937) published a work that assigned the currently-accepted scientific name, Tricholoma sciodes, to this mushroom.

The generic name Tricholoma signifies 'with hairs on the edge,' which is characteristic of only a minority of species within this genus.

As for the specific epithet, sciodes is derived from the Greek word "skiá," meaning shadow, giving the mushroom its name "shady."

Synonyms and Varieties

• Agaricus murinaceus sensu Cooke, auct.; fide Checklist of Basidiomycota of Great Britain and Ireland (2005)

• Agaricus myomyces var. γ sciodes Persoon (1801), Synopsis methodica fungorum, p. 346 (Basionyme)

• Tricholoma atrosquamosum subsp.* sciodes(Persoon) Konrad (1929), Bulletin de la Société mycologique de France, 45(1), p. 59

• Tricholoma murinaceum sensu Cooke, auct.; fide Checklist of Basidiomycota of Great Britain and Ireland (2005)

• Tricholoma sciodellum P.D. Orton, Kew Bull. 54(3): 709 (1999)[3]

• Tricholoma sciodes (Persoon) C. Martín (1919), Catalogue systématique des basidiomycètes charnus, des discomycètes, des tubérinées, des hypocréacées de la Suisse Romande, p. 51 (nom actuel)

• Tricholoma sciodes var. virgatoides Bon, Docums Mycol. 4(no. 14): 103 (1974)

• Tricholoma virgatum ss. Ricken (1914), Die Blätterpilze, p. 339, pl. 93, fig. 2

• Tricholoma virgatum var. sciodes (Persoon) Pilát (1961), Mushrooms and other Fungi, p. 69, pl. 69

Photo sources:

Photo 1 - Author: Jerzy Opioła (CC BY-SA 3.0)

Photo 2 - Author: Strobilomyces (CC BY-SA 3.0)

Photo 3 - Author: Lukas (CC BY-SA 2.0)

Photo 4 - Author: James Lindsey (CC BY-SA 2.0)