Name: Lactarius nanus
Author: J. Favre
Short description: Lactarius nanus is recognized by itstypically small size, gray-brown to liver brown pileustypically with a glaucous coating at least when young,cream to pinkish tan lamellae, pale cream-tan to paleapricot stipe, watery, unchanging latex, mild odor,mild to slightly acrid flavor and occurrence with Salixspecies in arctic-alpine areas.
Pileus 10–50 mm diam, shallowly convex to plano-convex becoming plane to infundibuliform with orwithout a depressed center and small papilla, smooth,slightly viscid to dry, with whitish glaucous coatingwhen immature, easily rubbing away or fading in age,often in patches, deep brown to gray-brown to liverbrown with lighter and darker areas present, oftenlighter toward margin, becoming lighter overall upondessication; margin straight when immature becomingupturned and wavy to convoluted when mature.Lamellae adnate to subdecurrent, subdistant to slightlycrowded, cream when immature becoming dingycream to light tan in age, sometimes with a faint pink-ish tinge, discoloring to dingy tan where damaged.Stipe 5–30 63–15 mm, equal to clavate, central,smooth, dry, at first covered with whitish glaucous coat-ing as in pileus, pale apricot to dingy cream-tan, hol-low. Latex scarce, watery, unchanging. Context ofpileus and stipe dingy cream to brownish. Odor mild.Flavor mild to slightly acrid. Basidiospore deposit notobserved. Basidiospores 7–10.5(–12) 65–8mm, av. 58.4 66.6 mm,Q51.07–1.60, Q¯51.27, hyaline in2.5% KOH, subglobose to ellipsoid; ornamentationof amyloid scattered ridges and warts forming anincomplete reticulum with some completely reticulateareas, to 0.7 mm high. Basidia 40.6–76.2 68.9–15.2 mm, mostly four-spored, some two-spored.Pleuromacrocystidia 53.3–96.5(–114.3) 66.4–11.4mm, lanceolate, with acute to moniliform apex,scattered to abundant. Cheilomacrocystidia 26.0–91.467.6–10.2 mm, subulate to linear with undulatingmargin, with acute to rounded apex, scattered toabundant. Pileipellis an (ixo-) cutis with some ascend-ing hyphae embedded in a very faint gelatinouslayer.
Distribution and habitat: Lactarius nanus originally wasdescribed by Jules Favre from the Swiss Alps with Salixherbacea L. (Favre 1955). Phylogenetic analyses includ-ing a specimen from near the type locality confirmthis species in the Rocky Mountain alpine zone, whereit is one of the most commonly encountered Lactariusspecies; it associates with Salix arctica,S. reticulata andS. planifolia. Overall L. nanus appears to be largelyrestricted to arctic-alpine areas with Salix.
(PDF) Systematics of the ectomycorrhizal genus Lactarius in the Rocky Mountain alpine zone. https://www.researchgate.net/...
Created: 2016-04-07 21:22:29 PDT (-0700) by Danny Newman (myxomop)
Last modified: 2018-12-27 22:24:07 PST (-0800) by Image Sharer (image sharer)
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