The Whitelaced Shank (Megacollybia platyphylla) is a common, fairly large grey-brown mushroom of broadleaf woodland, fruiting from late spring to autumn. Its streaky, radially fibrous cap often splits at the edge in dry weather, and the white gills are broad and widely spaced. It grows on rotting stumps, logs and buried wood, so it may seem to rise from the soil.
The clincher is at the base: dig carefully and you will find thick white mycelial cords, the 'laces', spreading into the surrounding litter and wood. It is the only Megacollybia species recorded in Britain. Edibility reports conflict, and some people have had stomach upsets, so it is best left for looking at.
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Distribution
Widespread and common
Habitat
On fallen logs and stumps of broadleaved trees or more rarely conifers
Etymology
Megacollybia means 'large Collybia', from Greek mega, 'large', and Collybia, from kollybos, 'small coin'. platyphylla is Greek for 'broad-leaved', after its very broad gills.
Cap
Cap 5-15 cm across, convex to flattened and sometimes slightly depressed. It is grey-brown and radially fibrillose, sometimes cracking or slightly squamose towards the centre, and the margin often splits in dry weather.
| Colour | |
|---|---|
| Shape | Convex, Flattened, Depressed |
| Surface | Fibrillose, Squamose |
| Width | 5 - 15 cm |
| Margin | Smooth, Split |
Gills
Very broad and widely spaced, becoming irregular and wavy in older specimens.
| Colour | |
|---|---|
| Attachment | Sinuate, Adnate |
| Spacing | distant |
Flesh
Thin and white.
| Colour | |
|---|---|
| Odour | Not distinctive |
| Taste | Mild |
Stem
Stem 5-15 cm long and 8-25 mm wide, cylindrical, white to pale mouse-grey and fibrillose, with no ring. There are prominent white, string-like mycelial cords at the base of the stem.
| Colour | |
|---|---|
| Height | 5 - 15 cm |
| Width | 8 - 25 mm |
| Texture | Fibrillose |
| Shape | Cylindric |
Spores
| Colour | |
|---|---|
| Shape | Broadly ellipsoid |
| Ornamentation | Smooth |
| Size | 6-10 x 5-8.5 μm |
Microscopic Features
The cheilocystidia are club-shaped (clavate) and measure 30-75 x 12-20 μm.
| Cheilocystidia | Club-shaped (Clavate) |
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Classification
- ↳ Phylum: Basidiomycota
- ↳ Subphylum: Agaricomycotina
- ↳ Class: Agaricomycetes
- ↳ Subclass: Agaricomycetidae
- ↳ Order: Agaricales
- ↳ Genus: Megacollybia
Synonyms
- Agaricus grammocephalus Bull.
- Agaricus platyphyllus Pers.
- Agaricus repens Fr.
- Agaricus tenuiceps Cooke & Massee
- Collybia grammocephala (Bull. ex Merat) Quel.
- Collybia grammocephala (Bull.) Quél.
- Collybia platyphylla
- Collybia platyphylla (Pers.) P. Kumm.
- Oudemansiella platyphylla (Pers. ex Fr.) Moser
- Oudemansiella platyphylla (Pers.) M.M. Moser
- Tricholoma tenuiceps (Cooke & Massee) Massee
- Tricholomopsis platyphylla (Pers. ex Fr.) Sing.
- Tricholomopsis platyphylla (Pers.) Singer
Reference Sources
T. Læssøe, J. H. Peterson (2019) Fungi of Temperate Europe Vol. 1. Princeton University Press.
G. Kibby (2020) Mushrooms and Toadstools of Britain & Europe Vol. 2. Geoffrey Kibby.
Genus Megacollybia
No other species found in this genus.
