The veiled species of Hebeloma in the western United States / Alexander H. Smith, Vera Stucky Evenson, and Duane H. Mitchel.

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The Veiled Species of Hebeloma

Stirps PASCUENSE
Stipe not darkening at the base.
KEY TO SPECIES
1. Spores 7-9 x 4.5-5 [xm; odor mild; cheilocystidia 26-37 (44) x 6-9
x 3-5 [xm; under spruce; pileus hoary at first and only slightly viscid
when mature..................................... H. urbanicola (r) (p. 181)
1. N o t as ab ove........................................................... 2
2. Odor and taste strongly raphanoid; stipe readily splitting lengthwise............................................. H. proximum (k) (p. 173)
2. Not as above......................................... 3
3. Pilear cuticle an ixocutis; stipe 2-5 mm thick; stipe white overall. 24. H. kauffmanii
3. N ot as above........................................................... 4
4. Hypodermium colorless in KOH; odor and taste more or less raphanoid............................................... H. pascuense (j) (p. 172)
4. N ot as above........................................................ 5
5. Pileus rimose in age; spores up to 7 pxm wide......... H. gregarium (e) (p. 167)
5. N ot as above........................................................... 6
6. Stipe 3-5 mm thick, cinnamon-buff; walls of hypodermial
hyphae with conspicuous incrustations (as revived in KOH)...................................................... 25. H. perigoense
6. Stipe 8-12 mm thick; hypodermial hyphae brown but incrustations
not prominent (if present) under a 54 x oil-immersion lens................................................. 26. H. subargillaceum
24. Hebeloma kauffmanii sp. nov.
Pileus 1.5-3 cm latus, convexus vel obtusus demum + planus vel
obtuse umbonatus, ad centrum subfulvus, ad marginem + alutaceus.
Contextus albus fragilis, odor nullus, sapor subnauseosus. Lamellae
demum emarginatae, confertae latae, cinnamomeae. Stipes 2-4 cm
longus, 3-4 mm crassus, solidus demum cavus, pallidus sericeus. Velum sparsum, fibrillosum, album. Sporae 8-10 (11) x 5-6.5 tIm, leves,
subinequilaterales, non dextrinoideae. Cheilocystidia filamentosa, cylindrica vel fusoide ventricosa, 38-63 x 3-7 x 2-3.5 Ixm subacuta,
obtusa vel (rare) subcapitata.
Specimen typicum in Herb. Univ. Mich. conservatum est, Kauffman 9-7-23; legit prope Centennial, Wyoming.
Pileus 1.5-3 cm broad, convex to obtuse, then + plane or with an
obtuse umbo, alutaceous or (on umbo) slightly tawny, subviscid, pellicle present; surface even, margin at first slightly white-cortinate. Context white when faded, thin, fragile, odor none, taste slight to subnauseous (Kauff. notes).