Amanita brunneoconulus - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita brunneoconulus
name status nomen acceptum
author Bas & Gröger
english name "Falsely Saccate Amanita"
intro The following is based on the original description of Amanita brunneoconulus.
cap The cap of A. brunneoconulus is 22 - 80 mm wide, hemispherical when young, plano-convex when mature, without an umbo, not viscid, with a rather broad, striate margin (25 - 33% of the radius). The cap is ochraceous brown, somewhat darker and slightly more reddish brown to olivaceous brown at the center, and paler at the margin. The flesh of the cap is up to 4.5 mm thick above the middle of the gills, white. The volva is present as small, truncate-conical volval warts which tend toward larger patches toward the cap''s margin. The volva is the same color as the cap but at first are paler than the background in the center. It is not easily removed from the cap.

gills The gills are free, crowded, up to 5 mm broad, sometimes forked, and whitish.  Near the cap's margin, the gills may have a brown edge.  The short gills are truncate and unevenly distributed.
stem The stem is 52 - 83 (-150) × 8 - 14 (-20) mm, stuffed, becoming hollow, slightly narrowing upwards, and exannulate.  The base is subbulbous.  On the base of the stem, one or two incomplete ridges of volva are present which cause a splitting of the stem's tissue, giving rise to an incomplete, false volva, 15 - 30 mm above the bottom of the stem, giving the subbulbous base a lobed appearance.  The flesh is predominantly white, but sometimes ochraceous at the base of the stem.
odor/taste Odor and taste are practically absent.
spores The spores measure (9.5-) 10.2 - 12.2 (-13.6) × (9.1-) 9.6 - 11.6 (-13.3) µm and are globose to subglobose and inamyloid.  Clamps are absent at bases of basidia.
discussion Originally described from Germany from deciduous forests including Beech (Fagus), Oak (Quercus), Basswood (Tilia), Ash (Fraxinus), and Crattaegus.

Bas and Gröger state the species is well-categorized based on the form of its volva, its colors, and its exannulate stem. Because of the subbulbous stem, Bas placed this species in section Amanita and suggested among its most similar taxa, A. friabilis (Karst.) Bas and A. hyperborea (Karst.) Fayod.  See also, for example, A. farinosa Schwein. and A. basiana Tulloss & M. Traverso.

Bas notes that the gelatization of the cap skin in this species is rather minimal.  This and the fact that the warts are difficult to remove suggests that connection between the warts and the cap skin remains unbroken well after the expansion of the fruiting body.  Amanita brunneoconulus has this character in common with the other species cited.—R. E. Tulloss
brief editors RET

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