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

4. Spores dextrinoid............................... Stirps Repandum (p. 40)
4. Spores not distinctly dextrinoid........................................ 5
5. Cuticle of pileus an ixotrichodermium rarely collapsing to an ixolattice
(study young pilei).......................... Stirps Pseudostrophosum (p. 41)
5. Not as above (cuticle rarely an ixolattice in age)............................ 6
6. Pileus and/or gills staining dark brown to blackish on some
basidiocarps in situ......................... Stirps Nigromaculatum (p. 50)
6. N ot staining as above................................................ 7
7. Stipe not darkening at base in age.................... Stirps Pascuense (p. 56)
7. Stipe soon darkening in basal area at least................................. 8
8. Stipe readily splitting lengthwise................... Stirps Dissiliens (p. 60)
8. Stipe not readily splitting...................... Stirps Mesophaeum (p. 61)
Stirps EVENSONIAE
Cheilocystidia with yellow amorphous content in KOH when
fresh; spores smooth.
8. Hebeloma evensoniae Smith & Mitchel sp. nov.
Illus. P1. 9.
Pileus (1.5) 2-4 (10) cm latus, obtusus demum convexus vel late
umbonatus, viscidus, ad marginem leviter fibrillosus, pallide ochraceus demum argillaceus; odor et gustus raphaninus. Lamellae confertae, adnatae, pallide ochraceae, serrulatae. Stipes 3-8.5 cm longus,
4-8 mm crassus, deorsum attenuatus vel radicatus, brunnescens. Velum copiosum, albofibrillosum. Sporae in cumulis "Vinaceous-Cinnamon," (7.5) 8.5-11.5 x 5.5-6 [(m, ovoideae vel ellipsoideae, leves,
non dextrinoideae. Cheilocystidia 34-49 x 5-9 [tm, fusoid-ventricosa,
chrysocystidiis similis. Fibulae adsunt.
Specimen typicum in Herb. Denver Bot. Garden conservatum
est, DBG 7948; legit prope "Poorman Gravel Pit," Sunshine, Boulder
County, Colorado, 22 May 1978, Vera Evenson.
Pileus 2-4 cm broad, obtuse to convex or broadly umbonate, surface viscid, margin at first with a thin coating of white veil fibrils, pale
cinnamon to + clay color where exposed, disc at times + ochraceoustawny. Odor and taste distinctly raphanoid. Context white, unchanging;
FeSO4 greenish on stipe base.
Lamellae broad, close, adnate, pale ochraceous becoming grayer
and finally dull cinnamon, edges serrulate, not beaded and not spotting.
Stipe 3-8.5 cm long, 4-8 mm thick, tapered to a ~ rooting