Lactarius dryadophilus Kühner

Jacob Heilmann-Clausen, Annemieke Verbeken & Jan Vesterholt, 1998, The Genus Lactarius, Copenhagen: Danish Mycological Society : 102

Lactarius dryadophilus Kühner

Lactarius dryadophilus Kühner , 1975a: 68. Holotype: Norway, Hardanger (LY). SYNONYM: Lactarius dryadophilus var. saliceticola Bon and Jamoni in Jamoni and Bon, 1992b: 21.

A medium-sized to large, lilac staining Lactarius with cream-coloured, viscid cap with a bearded margin; growing in arctic and alpine areas.

DESCRIPTION: Cap 30-100(-150) mm, at first convex with a slightly depressed centre and decurved or inrolled margin, sometimes slightly umbonate; surface sticky, viscid, at the margin bearded and tomentose with up to 2 mm long hairs, whitish chrome to pale cream or warm buff but more brownish in the centre, azonate or slightly zonate. Gills adnate, medium broad, crowded, often forked, whitish to pale cream, later pinkish buff. Stem 20-30 x 15-20 mm, typically curved and tapering downwards; surface whitish to pale cream, sometimes yellowish at the base, very finely pitted or with ochraceous spots, especially towards the base. Flesh firm, becoming hollow in the stem, white, changing to lilac; smell fruity, sweetish; taste mild, like cedar wood to very slightly acrid. Milk white, changing to lilac in contact with the flesh. Spore deposit cream.

Spores 9.3-11.8 x 7.2-9.2 um, av. 10.2-10.3 x 8.1-8.4 um, broadly ellipsoid to ellipsoid, Q = 1.15-1.40, av. 1.22-1.27; ornamentation up to 0.3 um high, of rather fine and narrow ridges, often aligned but not forming a reticulum or at most a very incomplete one; isolated warts often elongate; plage inamyloid. Basidia 60-70 x 12-15 um, subclavate, 4-spored. Pleuromacrocystidia moderately abundant, 80-120 x 10-15 um, fusiform, tapering to a mucronate apex. Gill edge sterile; cheilomacrocystidia 40-60 x 7-9 um, fusiform; paracystidia 10-25 x 4-6(-10) um; cylindric to tortuous or clavate. Pileipellis an ixocutis to an ixotrichoderm, 150-200 um thick; hyphae 1-5 um broad, very thin-walled and shrivelled, gelatinized, repent or ascending, some with conspicuous incrustations.

ECOLOGY AND DISTRIBUTION: Found in arctic and alpine vegetation types on rich, calcareous soils, often in Dryas-rich grasslands. Rather rare and known from Fennoscandia, the Alps, the Pyrenees and Greenland, and occuring from August to mid September.

DISCUSSION: The cap is tomentose only to a short distance from the margin, unlike in L. repraesentaneus , which also has more yellow colours, a longer stem and a different spore ornamentation.

The original description of L. groenlandicus was partly based on this species, but recently lectotypified as a synonym of L. pubescens (Knudsen nda Lamoure, 1993).