Amanita rhoadsii - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita rhoadsii
name status nomen acceptum
author (Murrill) Murrill
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  • 1. Amanita rhoadsii



  • 2. Amanita rhoadsii

  • Amanita rhoadsii (Murr.) Murr. var. rhoadsiiAmanita rhoadsii (Murr.) Murr. var. rhoadsii

    3. Amanita rhoadsii (Murr.) Murr. var. rhoadsii

  • intro Amanita rhoadsii has very narrow spores, which commonly may be more than 4 times as long as they are wide.
    cap The cap is white and 50 - 100 mm wide.
    gills The gills are white to cream to yellowish cream, adnate or adnexed, and moderately crowded to crowded.  The short gills are subtruncate to attenuate.
    stem The exannulate stipe is 70 - 180 × 7 - 20 mm and, at first, densely floccose; at the stipe base is an elongate bulb.  There are rarely any volval remnants at the top of the stipe's basal bulb.
    odor/taste Amanita rhoadsii has a distinctive odor (some authors call it "old ham"), not of chlorine, but quite difficult to describe.  A yellow-staining var. (A. rhoadsii var. flavotingens Bas) has been described.
    spores The spores measure (9.8-) 10.1 - 14.5 (-15.5) × (3.5-) 3.8 - 4.8 µm and are cylindric to bacilliform (even, infrequently, more than four times longer than wide!) and amyloid.  Clamps are present on bases of basidia.
    discussion Because, the closely related A. subsolitaria (Murrill) Murrill is occasionally found strongly staining yellow and obviously parasitized by something, it would be a worthwhile project to find yellow-staining A. rhoadsii and examine them for an environmental cause of the reaction.  The yellow staining members of A. rhoadsii were placed in A. rhoadsii var. flavotingens BasAmanita rhoadsii and A. subsolitaria make up Bas' stirps Rhoadsii.

    Amanita rhoadsii is often associated with oak and pine.

    Amanita rhoadsii is moderately common in the southern part of the sandy Atlantic coastal plain of the U.S. and along the U.S. Gulf Coast.  A. subsolitaria has an overlapping range, and has been collected as far north as Cape Cod.—R. E. Tulloss
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