Amanita elliptosperma - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita elliptosperma
name status nomen acceptum
author G. F. Atk.
english name "Atkinson's Destroying Angel"
images
  • Amanita hygroscopica (pale pink gills) - Alpena, WV, USA - RETAmanita hygroscopica (pale pink gills) - Alpena, WV, USA - RET

    1. Amanita hygroscopica (pale pink gills) - Alpena, WV, USA - RET

  • Amanita hygroscopica - bulb and limb, West Virginia, USAAmanita hygroscopica - bulb and limb, West Virginia, USA

    2. Amanita hygroscopica - bulb and limb, West Virginia, U.S.A..



  • 3. Amanita elliptosperma, Griffey Lk., Bloomington, Monroe Co., Indiana, U.S.A.

    • intro

    The following description is based on Atkinson (1909) and Jenkins (1982), with the addition of my observations of the type and a few additional collections.

    This species' name is the earliest in the group of North and Central American taxa with white fruiting bodies, ellipsoid spores, and thin membranous (not felted) partial veils.  See the key including such taxa of the cited region here.

    cap

    The cap of Amanita elliptosperma is 38 - 84 mm wide, hemispheric at first, becoming convex, then plano-convex, and finally concave (upward flaring margin); it is white, sometimes with a tinge of cream color in the center. The cap context is 3 - 7 mm thick over the stem and thins evenly to the margin.  The cap margin is smooth and not appendiculate.  No remnants of the volva are present.

    gills

    The gills are free to narrowly adnate (sometimes with small decurrent tooth, but without a decurrent line on the upper stem) and crowded, off-white to dingy cream to pinkish in mass, and off-white to dingy cream to yellowish white in side view, and 5 - 6 mm broad.  They are roughly lozenge-shaped and do not change color when bruised or broken.  The short gills are rounded truncate to subtruncte to subattenuate to attenuate to attenuate in steps, very plentiful, of diverse lengths, and unevenly distributed.

    stem The stem is 35 - 115 × 5 - 11 mm, tapering upward, solid. The basal bulb is ovoid and 19 - 42 × 16 - 33 mm. The ring is ample or torn in shreds, apical, skirt-like, membranous, and thin. The volva is ample, membranous, limbate, and more or less lobed.  The highest point of the volva limb is 26 - 63 mm from the bulb's bottom.
    odor/taste This species should be assumed to be deadly POISONOUS.
    spores

    Spores of the type of A. elliptosperma measure (8.0-) 8.7 - 11.2 (-11.5) × (5.8-) 5.9 - 7.5 (-7.8) µm and are ellipsoid (infrequently elongate) and amyloid. Clamps are absent from bases of basidia.

    discussion Originally described from North Carolina, USA.  With a range probably extending from southern New England to the Gulf Coast and eastern Texas.

    Amanita elliptosperma is the oldest available name in the group of taxa with thin and membranous annulus and ellipsoid spores. Amanita magnivelaris Peck can be distinguished by a proportionately large, relatively thick and felted ring. RET has distinguished a taxon similar to A. elliptosperma (but with narrower spores) as a separate species (Amanita sp-S04), but this may be an error.  If so, the spore widths of the combined material would extend down to 4.9 µm.—R. E. Tulloss

    brief editors RET

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