Amanita basiorubra - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita basiorubra
name status nomen acceptum
author O. K. Mill.
english name "Red Anklet Amanita"
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  • 1. Amanita basiorubra, Western Australia, Australia.



  • 2. Amanita basiorubra, Western Australia, Australia.


  • 3. Amanita basiorubra, stipe base and upper part of bulb with red anklet, Western Australia, Australia.

    • intro The following is based on the original description of Miller (1992).
    cap

    The cap of Amanita basiorubra is 38 - 70 mm wide, convex to broadly convex, nearly plane in age, viscid, often sand covered, smooth, brown, light brown to brownish-orange in age, with a nonstriate margin. The volval remnants are present as small, filmy patches of white, tinted pink to reddish and concentrated over the center. The red coloring apparently comes from remains of a floccose-fibrillose red surface layer of the volva that may be more clearly seen on the edge of the ring and at the stem base. The margin is often covered with scattered, small patches with fine, pink fibrils. The flesh is white.

    gills

    The gills are narrowly adnate, close to subdistant, narrow, pure white, with smooth edges. Short gills make up a single tier.

    stem

    The stem is 50 - 85 × 8 - 18 mm, white, cylindric or narrowing upward. The volva is filmy, white with an outer covering of thin, red fibrils and scattered with pieces of the volva that are more apparent on the edge of the ring and near the base of the stem in age. The basal bulb is clavate to submarginate to marginate, sometimes turnip-shaped, with a reddish zone over the top half of the bulb comprising red floccose-fibrillose "tufts," more or less thickened. The ring is persistent, white, skirt-like, membranous, with a thin rim of red-tipped fibrils at the edge. The flesh is white in the upper stem, with reddish pigment in the stem base in most specimens, at all ages.

    odor/taste

    No odor is present.

    Miller reports this species as easily cultured.

    spores

    The spores measure 7.6 - 9 × 5.5 - 6.7 µm and are broadly ellipsoid to ellipsoid and amyloid. Clamps are probably absent at bases of basidia.

    discussion

    Originally described from the state of Western Australia under Eucalyptus and Allocasuarina. It is only known from that region.

    Miller points out the very unusual nature of the volva in this species. In section Validae the volva is friable but usually significantly more dense than the floccose-fibrillose volva described for A. basiorubra. The volva's apparently double-layered nature and the inconsistency of pigmentation in even those cells of the largely red layer are two very distinctive characters. This species has no obvious close relative among the others within section Validae.

    One wonders if Miller's interpretation of the cap as viscid is because sand was retained by it. The cap skin may not quickly separate from the volva in this species as often is the case when a filmy lower layer of the volva is reported. Sand may be caught in the plentiful hyphae of the volva.—R. E. Tulloss

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