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

Habit, habitat, and distribution.-On soil under conifers, Independence Pass area, Pitkin County, Colorado, August 4, 1976, Smith
87043 (type, MICH).
Observations.-H. nigromaculatum is a second species which develops blackish spots on the pileus, but it is readily distinguished from
H. substrophosum by the narrower stipe, hyphoid hypodermium and in
having an ixocutis over the pileus. H. substrophosum appears to be
closely related to H. fastibile sensu Horak, but again, as with H. pseudostrophosum, the presence of an ixotrichodermium over the pileus is
distinctive.
16. Hebeloma vinaceoumbrinum sp. nov.
Illus. Figs. 11-12.
Pileus (1) 2-3 cm latus, late convexus vel umbonatus, glaber,
viscidus, atrovinaceus dem obscure testaceus, ad marginem fibrillosus;
odor et gustus raphaninus. Lamellae pallidae, tarde cinnamomeae,
confertae, latae, adnatae. Stipes 4-7 cm longus, 3-5 mm crassus, albidus, brunnescens. Velum albidum, fibrillosum, evanescens. Sporae
7.5-10 x 5-6 VLm,. non dextrinoideae, ellipsoideae vel ovoideae.
Cheilocystidia 38-56 x 6-9 x 4-6 pim, obtusa. Cuticula pileorum
ixotrichoderma est.
Specimen typicum in Herb. Univ. Mich. conservatum est; Smith
89950; legit sub Alni, prope Burnt Mt., Pitkin County, Colorado, 25
Aug 1979.
Pileus (1) 2-3 cm broad, convex becoming broadly convex, sometimes obtusely umbonate, disc glabrous and viscid, deep vinaceousbrown ("Natal Brown") becoming paler to "Army Brown" or redder;
margin white fibrillose from remains of the veil, edge often fringed
with fibrils. Context watery grayish, fading to white; odor and taste
raphanoid; FeSO4 on base of stipe olivaceous.
Lamellae broad, close, adnate, whitish at first as seen across the
gills, faces at first avellaneous becoming dull cinnamon; edges not
beaded and not spotted.
Stipe 4-7 cm long, 3-5 mm thick, equal, solid, white and fibrillose overall at first but veil white and not leaving an annulus; near base
soon becoming brown and the change progressing upward (the FeSO4
color change most pronounced on the discolored area).
Spores 7.5-10 x 5-6 Ixm, smooth in KOH, minutely punctate in
Melzer's, not dextrinoid, in face view ovate to elliptic, in profile ovate
to elliptic (not inequilateral to any degree).
Hymenium.-Basidia 4-spored, narrowly clavate, 7-9 VLm broad,