Russula illota

Description

Russula illota is an inedible species of mushroom in the genus Russula. The cap is spherical when young, later broadly convex, and can be flat when old. It is dull ochre and covered in a grey slime, up to 15 cm in diameter. The gills are pale cream and close together, giving off a scent of bitter almonds when rubbed. The stem is white and becomes blotchy with age. It is commonly found in deciduous and coniferous forests on chalk. Habitat in some parts of Europe and North America.

Common names: Freckled Brittlegill.

Mushroom Identification

1. Cap

   5 to 15 cm in diameter and more or less flat or slightly depressed in the center when fully developed, the caps are spherical when young. The cap surface is viscid and develops intense radial ridges.

2. Gills

   The narrow, adnexed gills are moderately close together; they are very brittle. Initially, cream, the gills darken with age and their edges develop violaceous-brown 'dots and dashes'.

3. Stem

   15 to 35mm in diameter and 4 to 8cm tall, the stems are white and solid, developing internal cavities; vinaceous-brown dashes develop longitudinally down the stems as they age.

4. Spores

   Ellipsoidal, 8-9 x 6.5-7.5µm, ornamented with sharp warts up to 1.2µm tall with a few connecting lines but not forming a reticulum.

5. Spore Print

   Cream.

6. Odor and Taste

   Very variable (often in between Russula grata and Russula foetens) and so not generally of much help with identification.

7. Habitat & Ecological Role

   Coniferous and broadleaf woodland, most often on chalky soil. In common with other members of the Russulaceae, Russula illota is an ectomycorrhizal mushroom.

Look-Alikes

1. Russula laurocerasi

   Is not yet technically distinguished from this species.

2. Russula grata and Russula foetens

   Similar to Russula illota in appearance, habitat and season. Few people can tell these three fungi apart with any certainty without resorting to microscopic examination.

History

The Freckled Brittlegill was described in 1954 by French mycologist Henri Charles Louis Romagnesi (1912 - 1999), who gave it the scientific name Russula illota by which it is generally recognized today.

Russula, the generic name, means red or reddish, and indeed many of the brittlegills do have reddish caps.

The specific epithet illota means dirty or unwashed - a reference to the freckled appearance of caps of this brittlegill.

Photo sources:

Photo 1 - Author: federicocalledda (CC BY-NC 4.0)

Photo 2 - Author: federicocalledda (CC BY-NC 4.0)

Photo 3 - Author: marcofloriani (CC BY-NC 4.0)