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

The Subgenus Hebeloma

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87. Hebeloma perfarinaceum sp. nov.
Pileus 1-2.5 cm latus, obtusus demum obtuse umbonatus;
glaber, subviscidus, griseobrunneus demum sordide rufobrunneus.
Contextus pallidus, odor nullus, sapor valde farinaceus. Lamellae
latae, adnatae, pallide avellaneae demum griseobrunneae vel sordide
cinnamomeae. Stipes 2.5-4 cm longus, 3-5 mm crassus, aequalis,
albus, demum brunneus ad basin. Velum pallidum. Sporae 12-14 x
6.5-7.5 pJm, inequilaterales, non dextrinoideae vel tarde subdextrinoideae. Basidia tetraspora, in Melzer's rubra. Cheilocystidia 40-70
(100) x 4-7 Im, cylindrica vel filamentosa, vel anguste ventricosa ad
basin, ad apicum obtusa.
Specimen typicum in Herb. Univ. Mich. conservatum est, Smith
90421; legit prope Elk Wallow, Fryingpan River, Pitkin County, Colorado, 29 Jul 1980.
Pileus 1-2.5 cm broad, obtuse becoming expanded umbonate,
margin decurved and with a thin coating of veil fibrils; surface glabrous, scarcely hygrophanous, subviscidus, "Wood Brown" (brownish
gray) becoming "Verona Brown" (dull reddish brown), opaque when
fresh. Context pallid, odor slight, taste distinctly farinaceous, FeSO4
staining base of stipe dark olive.
Lamellae close, broad, adnate, horizontal, pale avellaneous to
wood brown and finally dull cinnamon ("Sayal Brown"), not beaded
or spotted.
Stipe 2.5-4 cm long, 3-5 mm thick, equal, evenly dull white
overall but soon brunnescent in the base; surface pallid from whitish
veil, apex at most only faintly pruinose.
Spores 12-14 x 6.5-7.5 im, appearing smooth under a high-dry
objective, inequilateral in profile, ovate in face view, when fresh
slowly weakly dextrinoid, after being dried and standing in the herbarium slightly more dextrinoid.
Hymenium.-Basidia 4-spored, 8-10 LTm broad, containing hyaline "oil" droplets; hymenium slowly becoming red in Melzer's. Cheilocystidia 40-70 (100) x 4-7 [Lm, cylindric to filamentous (straight or
flexuous), or narrowly fusoid-ventricose, apex not enlarged, rarely
branched, hyaline in KOH. Pleurocystidia none.
Lamellar and pilear tissues.-Lamellar trama typical of the genus
but in Melzer's slowly becoming flushed red. Cuticle of pileus an ixocutis, the hyphae tubular and 2-5 iLm diam, clamped. Hypodermium
hyphoid, poorly differentiated, pigment deposits scattered on the hyphal walls. Tramal hyphae typical of the genus but not red in Melzer's;
dextrinoid debris present in an irregular pattern.
Habit, habitat, and distribution.-Clustered under spruce above