Amanita sp-10 - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita sp-10
name status cryptonomen temporarium
author Tulloss
english name "Brown-Haired Yellow Dust Amanita"
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  • Amanita sp-10, Princeton Univ. ca. Graduate College and Golf Course, Mercer Co., New Jersey, U.S.A.Amanita sp-10, Princeton Univ. ca. Graduate College and Golf Course, Mercer Co., New Jersey, U.S.A.

    1. Amanita sp-10, Princeton Univ. ca. Graduate College and Golf Course, Mercer Co., New Jersey, U.S.A.

    • cap The cap of this species is 40–105 mm wide, at first solidly pigmented dark brown, becoming streaked with brown on a gray-tan ground color, darkest over disc, and sometimes with a yellow tint at first.  The cap is hemispheric at first with or without an incurved margin; it then becomes broadly convex to planar and is sometimes depressed in age.  It is dull to subshiny and tacky when moist, subshiny to subsilky when dry.  Its flesh is white and not changing when cut or bruised; in particular, there is no yellow reaction when the pileipellis is scraped away in the cap's center.  The margin is nonstriate or short striate (sometimes even before partial veil separation) and not appendiculate.  The volval remnants on the cap are yellow warts (occasionally in groups) or crumbs or small patches, minutely warty, flocculose, easily crushed, easily removed, and fading to pale yellow then tan or grayish and finally brownish in age.
    gills The gills are free to narrowly adnate, without a decurrent line on the upper stem, crowded, off-white to pale cream in mass, white in side view, unchanging when cut or bruised or infrequently with brown spots, and thin.  The short gills are predominantly attenuate (occasionally truncate), plentiful, unevenly distributed, and of diverse lengths.
    stem The stem is 33–93 × 8–14 mm, whitish, sometimes pale yellow in some parts, becoming grayish or brownish from age and handling.  The bulb at the stipe's base is 10+–29 × 9–25 mm, as white or whiter than palest part of stipe, ovoid to subnapiform to narrowly fusiform, sometimes with a little "root" on the bottom.  The stem's flesh is off-white, usually solid to firmly stuffed at first, sometimes mostly hollow, sometimes becoming pinkish brown to slightly orangish brown or brown when damaged by insects, and with its central cylinder 1–4 mm wide.  The stipe's ring is pale yellow, superior, membranous, skirt-like, thin, smooth above and below, has an edge thickened by yellow universal veil material, becomes darker in age and finally collapses. Volval remnants are present as yellow warts on the lower stipe and the upper part of the bulb; they can easily be lost during collecting. Occasionally there is a thin partial ring of yellow volval material on the stipe close to the top of the bulb.
    odor/taste The odor is indistinct to slightly earthy.
    spores The spores measure 7.0 - 9.1 (-9.4) × (4.9-) 5.2 - 6.3 µm and are ellipsoid (infrequently either broadly ellipsoid or elongate) and amyloid.  Clamp information t.b.d., probably very rare to absent.
    discussion This species is distinguishable in eastern North America by having a bulb that is like that of A. flavoconia G. F. Atk. rather than that of A. brunnescens G. F. Atk.; yellow volval material; a white stipe and annulus; and a brown, virgate cap. Specimens infected with Hypomyces hyalinus(Schwein.) Tul. & C. Tul. have been found on the grounds of Princeton University.—R. E. Tulloss
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