Amanita whetstoneae - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita whetstoneae
name status nomen provisorum
author Tulloss, Goldman and Kudzma
english name "Whetstone's Amidella"
images
  • Amanita whetstoneae, ?, U.S.A.Amanita whetstoneae, ?, U.S.A.

    1. Amanita whetstoneae, ?, U.S.A.

  • Amanita whetstoneae, Nantahalla National Forest, North Carolina, U.S.A.Amanita whetstoneae, Nantahalla National Forest, North Carolina, U.S.A.

    2. Amanita whetstoneae, Nantahalla National Forest, North Carolina, U.S.A.

  • Amanita whetstoneae, Forest 44 Conservation Area, St. Louis Co., Missouri, U.S.A. (RET 500-4).Amanita whetstoneae, Forest 44 Conservation Area, St. Louis Co., Missouri, U.S.A. (RET 500-4).

    3. Amanita whetstoneae, Forest 44 Conservation Area, St. Louis Co., Missouri, U.S.A. (RET 500-4).

  • intro The following is based on original research of RET.
    cap The cap tends to become tannish with age and is the only known taxon among North American species of section Amidella to do so.
    stem The stem is long and sometimes sinuous and lacks an annulus.  The volval sack is notably elongated and tubular,
    spores The spores measure (7.0-) 8.8 - 12.0 (-14.1) × (4.2-) 4.8 - 6.5 (-8.2) µm and are ellipsoid to elongate to cylindric (rarely broadly ellipsoid) and amyloid.  Clamps are not to be found at the bases of basidia.
    discussion Brick-red staining of the volva or other parts of the fruiting body with injury, exposure, or age is not prominent in this species.  The only other taxon in section Amidella in North America with such a weak oxidation reaction is Amanita peckiana Kauffman.  This latter species has spores that are dominantly cylindric and, early in the mushroom's expansion, it has a delicate, but distinct, ring.  A ring is always absent in A. whetstoneae.

    The present species is uncommon, but locally plentiful.  This is the tallest species in section Amidella in N. America (although all "large" taxa can have occasional, smaller fruiting bodies).—R. E. Tulloss

    brief editors RET

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