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[ Section Validae page. ] [ Amanita Studies home. ] [ Keys & Checklist/Picturebooks ] Amanita media Dav. T. Jenkins"White Fence-Sitting Amanita"
Technical description (t.b.d.) BRIEF DESCRIPTION: The following description is based on Jenkins (1983). The cap of Amanita media is up to 78 mm wide, plano-convex with a slight depression in the center, shiny, smooth, silvery white, with a nonstriate margin. The volval remnants are present as a few, small, floccose patches. The flesh is white and up to 7 mm thick over the stem. The gills are adnexed, crowded, creamy white; the short gills are truncate to slightly attenuate. The stem is up to 50 × 14 -15 mm, solid, creamy-white, smooth, with random, white, easily removed, floccose patches of volva on the upper bulb, sometimes in rather large, easily broken patches, and sometimes forming a low rim on the base of the stem. The basal bulb is egg-shaped, with narrow end down, with the top of the bulb somewhat flattened (subabrupt) up to 30 × 25 mm. The ring is apical, white delicate, soon disappearing. The spores measure (9.4) 10.2 - 12.5 × 4.7 - 5.5 µm and are elongate to cylindric and amyloid. Clamps are absent at bases of basidia. Amanita media was originally described from Alabama, USA, where it occurs among loblolly pine and mixed hardwoods. Jenkins notes that A. media is hard to place -- "intermediate between sections Lepidella and Validae"
as in the case of A. radiata Dav. T. Jenkins. The cylindric spores and delicate partial veil
suggested section Lepidella to Jenkins but the nonappendiculate
pileus margin and the form of the volva suggested section Validae
to him. A more extensive discussion of "borderline" taxa can
be found on the page for Amanita radiata (link above). As in that case, Amanita
media has a noncellular subhymenium which could argue for its placement in section Lepidella. [ Section Validae page. ] [ Amanita Studies home. ] [ Keys & Checklist/Picturebooks ] Last changed 21 January 2009. |