Lactarius mairei
What You Should Know
Lactarius mairei is a member of the large milk-cap genus Lactarius in the order Russulales. It has an ocher-brown mushroom with a hairy cap. It is a common species on calcareous soils under oak trees and occurs in August-October.
In some parts of Europe, this mushroom is edible if cooked well. But in most cases, it is described as a toxic species that can cause severe gastrointestinal disorders with diarrhea and vomiting.
Originally found in Morocco, it was described as new to science in 1939 by Georges Jean Louis Malençon.
Other names: Whiskery Milkcap, Lactaire à poil ras, Lactaire de Maire (France), Braunzottiger Milchling (German).
Lactarius mairei Mushroom Identification
Cap
2.5 - 12 cm, first convex, concave in the middle, with a tucked edge, later convex outstretched, concave, with a lowered or straight edge. The surface of the cap is hairy with spines up to 5 mm long, along the edge, dry, pale yellow-cream, pale clay-cream, yellow-brown, concentrically zonal, with darker, clay-brown zones.
Gills
The gills are ingrown, or slightly descending on the leg, thick, branched, and cream.
Stem
1.5 - 4 cm high, 0.5 - 1.5 cm in diameter, cylindrical, smooth, dry, initially solid, with age with cavities, pale cream, cream, yellowish-brownish-cream, yellowish-pinkish-cream.
Flesh
The flesh is whitish, burning in taste, with a faint fruity or bedbug odor. Milk juice does not change color, initially neutral, after a few seconds burning and pungent taste.
Spores
5.9-9.0 * 4.8-7.0 μm, elliptical or almost rounded, with ornamented warts or ridges.
Spore Print
Cream.
Habitat
Grows from August to October, in deciduous forests, on limestone soils, in small groups, and rarely forms mycorrhiza with oak.
Lactarius mairei Look-Alikes
Lactarius mairei
Has a similar habitat and visible hairy caps.
Lactarius citriolens
Has yellowing milk, unlike L. mairei with white. This species can interact with different trees.
Lactarius tesquorum
Grows in association with cysts (Cistus) in Mediterranean habitats.
Lactarius mairei Synonyms
Lactarius zonatus (A. Pearson) J. Blum, 1964
Lactarius pearsonii Z. Schaef., 1966
Lactarius mairei var. ilicis Lalli & Pacioni, 1989
Lactarius pearsonii
Sources:
Photo 1 - Author: Lukas from London, England (Creative Commons Attribution-Share Alike 2.0 Generic)
Photo 2 - Author: Irene Andersson (irenea) (Creative Commons Attribution-Share Alike 3.0 Unported)