Amanita subnigra - Amanitaceae.org - Taxonomy and Morphology of Amanita and Limacella
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name Amanita subnigra
name status nomen provisorum
author Lamoureux
english name "Lamoureux's Dark-capped Ringless Amanita"
images
intro The information on this page is derived from (Lamoureux 2006) and from original research of RET.
cap The cap of Amanita subnigra is 40 - 80 mm wide and dark yellowish brown to ochraceous brown to somewhat olivaceous dark brown to brown black.  Sometimes darkest over the center and in a zone at the inner ends of the marginal striations.  At first it is ovoid to rounded-conic to bell-shaped; it becomes flattened convex and umbonate.  Its flesh is white except for a brown line below the cap's skin (most noticeable above the stem); the flesh does not stain or bruise.  Its edge bears long radial grooves that extend for 35 to 45% of the cap's radius.  No remnants of the volval are present on the cap.
gills The gills of this species are free, crowded, pale grayish to whitish to cream to slightly orangish cream in mass and cream in side view.  They do not stain or bruise; the are up to about 4 mm broad at three-quarters of the gill length from the stem.  They have a white minutely powdery edge.  The plentiful short gills are truncate to subtruncate, unevenly distributed, and of diverse lengths.
stem The off-white to cream, ringless stem of A. subnigra is 60 - 140 × 5 -15 mm, narrows upward, and is smooth to satiny or decorated with scattered fibrils.  Its flesh is white to off-white and stuffed becoming hollow (with central cylinder 5+ mm wide).  The soft, membranous, sack-like volva (35 × 33 mm) is white and sometimes bears scattered brown or ochraceous spots on its exterior.
truffle-like fruiting body double click in markup mode to edit.
odor/taste This species is odorless.  Its taste has not been recorded.
spores The spores of A. subnigra measure 10.0 - 11.4 (-12.4) × (8.1-) 8.5 - 9.8 (-11.0) μm and are subglobose to broadly ellipsoid to ellipsoid and inamyloid.  Clamps are absent from bases of basidia.
discussion This species is known from the Island of Newfoundland, the Province of Québec, and the U.S. state of Minnesota.  Lamoureux reports it from Spruce (Picea) plantations.  It also is found on limestone barrens possibly associated with Balsam Fir (Abies balsamica) or Spruce and in humus of mixed forest including Red Pine (Pinus resinosa), Birch (Betula), and Poplar (Populus), with some Black Spruce (Picea mariana) bogs.—Y. Lamoureux and R. E. Tulloss
brief editors RET

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