Russula insignis is a small to medium brittlegill with a greyish-brown to clay-buff cap, 3.5-7 cm across, which is sticky when fresh and finely granular. The cap edge becomes grooved and often splits as it ages, and the skin peels back about halfway. The gills are cream and close, often marked with reddish-brown spots, and the white stem stains reddish-brown and can be yellowish towards the base. The smell is fruity or faintly floral and the taste mild, slightly oily.
It is occasional but widespread in the UK, fruiting from July to October on the ground under broadleaf trees, especially beech.
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Distribution
Occasional but widespread
Habitat
Under broadleaf trees, especially Fagus
Etymology
Russula comes from Latin russus, meaning red, via the Late Latin russulus, meaning reddish. It refers to the red caps of many brittlegills, though this species has a greyish-brown cap. The epithet insignis is Latin for distinguished or remarkable. No source explains why Quélet chose it for this fungus.
Associates
Fagus
Cap
The cap surface is covered in fine granules, which are encrusted and give it a slightly rough, finely granular look. It is sticky when fresh, so the granules may be easiest to see on a dry or older cap.
| Colour | |
|---|---|
| Width | 3.5 - 7 cm |
| Peeling | 1/2 |
Gills
The cream, closely spaced gills are often spotted with reddish-brown. Look for these marks on older fruit bodies, as they help to separate this species from other pale brittlegills.
| Colour | |
|---|---|
| Spacing | close |
Flesh
The flesh is mild with a slightly oily taste and a fruity or faintly floral smell. Cut or handled stem tissue turns reddish-brown, and the stem base often has a yellowish tint.
| Odour | Fruity or slightly floral |
|---|---|
| Taste | Mild, slightly oily |
Stem
The stem is white, sometimes flushed grey, and often tinted yellow towards the base. It stains reddish-brown where it is handled or cut, so check for this when you collect a specimen.
| Colour | |
|---|---|
| Bruising |
Macrochemicals
Guaiac turns the flesh blue, which is a useful positive reaction. KOH gives a scarlet colour and iron sulphate (FeSO4) a pinkish-buff one.
| KOH | |
|---|---|
| FeSO4 | |
| Guaiac |
Spores
The spores are subglobose, 6.5-8 x 5-6 µm, and ornamented with warts up to 0.6 µm tall. Some of the warts are joined by low connecting ridges, which form an irregular, partial network. The spore print is white.
| Colour | |
|---|---|
| Size | 6.5-8 x 5-6 μm |
Microscopic Features
The pileocystidia, the cystidia in the cap skin, are encrusted. This feature is seen in a microscope mount of the cap surface.
Classification
- ↳ Phylum: Basidiomycota
- ↳ Subphylum: Agaricomycotina
- ↳ Class: Agaricomycetes
- ↳ Order: Russulales
- ↳ Family: Russulaceae
- ↳ Genus: Russula
Synonyms
- Russula insignis Burl.
- Russula livescens sensu Lange [Fl. Ag. Dan. 5: 66 & pl. 185A (1940)]
- Russula livescens var. depauperata J. Lange
- Russula livescens var. depauperata J.E. Lange
- Russula pectinata var. insignis (Quél.) Maire
- Russula pectinatoides sensu Dennis, Orton & Hora [TBMS 43(Suppl.), 1960], sensu Rayner (1985)
Reference Sources
G. Kibby, M. Tortelli, F. Hampe, C. V. Soler (2026) The Genus Russula in Great Britain with keys to species. Geoffrey Kibby.
