The Fragile Brittlegill (Russula fragilis) lives up to its name: the whole fungus is so brittle that it is hard to find an unbroken specimen. The small cap is variable in colour, usually violet to purple with a greenish or darker centre, and has a grooved margin. The white gills have tiny notched edges, visible with a hand lens, which is the best way to separate it from similar small brittlegills.
It has a fruity smell, sometimes likened to coconut, and a very hot taste. It grows in both broadleaf and conifer woodland from summer into autumn. The Birch Brittlegill (Russula betularum) and Slender Brittlegill (Russula gracillima) grow with birch and lack the notched gill edges. It is not poisonous, but its hot taste makes it inedible.
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Distribution
Common and widespread
Habitat
In both broadleaved and coniferous habitats
Etymology
Russula is a diminutive of the Latin russus, 'reddish', after the red caps of many species. fragilis is Latin for 'fragile', after its very brittle flesh.
Associates
Quercus
Conservation
Cap
The cap is 2-6 cm across, convex to flattened, smooth and viscid, with a grooved (sulcate) margin. The colour is variable, from lilac and purple to dark violet or greenish-grey, and the cap is very fragile, with the cuticle peeling about 70% of the way in.
| Colour | |
|---|---|
| Shape | Convex, Flattened |
| Surface | Smooth, Viscid |
| Width | 2 - 6 cm |
| Margin | Sulcate |
| Peeling | 7/10 |
Gills
White, brittle and fairly widely spaced, with minutely notched edges (use a hand lens).
| Colour | |
|---|---|
| Spacing | subdistant |
| Edge | serrated |
Flesh
White and extremely brittle.
| Colour | |
|---|---|
| Odour | Pleasant of coconut mixed with fruit |
| Taste | Very acrid |
Stem
The stem is white, cylindrical and smooth, very spongy and fragile, and slightly yellow at the base. It is especially brittle at the slightly swollen base and has no ring.
| Colour | |
|---|---|
| Texture | Smooth |
| Shape | Cylindric |
Macrochemicals
The guaiac reaction is nil to very pale blue (greyish-blue). FeSO4 (iron salts) gives a flesh-pink reaction.
| FeSO4 | |
|---|---|
| Guaiac |
Spores
The spores are subglobose, 7.5-9 x 6-8 μm, with warts up to 0.5μm high and a well-developed reticulum.
| Colour | |
|---|---|
| Shape | Subglobose |
| Ornamentation | Reticulate, Warty |
| Size | 7.5-9 x 6-8 μm |
Microscopic Features
Dermatocystidia are abundant, club-shaped (clavate) to cylindrical, septate, with 0-2 septa.
| Dermatocystidia | Club-shaped (Clavate), Cylindrical, Septate |
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Classification
- ↳ Phylum: Basidiomycota
- ↳ Subphylum: Agaricomycotina
- ↳ Class: Agaricomycetes
- ↳ Order: Russulales
- ↳ Family: Russulaceae
- ↳ Genus: Russula
Synonyms
- Russula bataillea
- Russula fragilis (Pers. ex Fr.) Fr.
- Russula fragilis (Pers.) Fr.
Reference Sources
T. Læssøe, J. H. Peterson (2019) Fungi of Temperate Europe Vol. 1. Princeton University Press.
G. Kibby (2021) The Genus Russula in Great Britain. Geoffrey Kibby.
