The cap of A. huijsmanii is 45 - 60 mm wide,
subcampanulate at first, then convex, with a distinct
broad umbo in some specimens, dry, with a strongly
striate margin (25±% of the radius); the cap
is metallic gray, occasionally slightly darker in the
disc. The volva is usually absent.
The gills are free, not too close, white with a flesh-cream tone in mass in
mature specimens, and rounded at the cap margin. The
short gills are truncate at a right angle or at a slight slant.
The stem is 55 - 70 × 7 - 9 mm, white, narrowing slightly and evenly upward,
ornamented with fine white fibrils, and exannulate. The
flesh is white and hollow. The volva is membranous,
white, and often completely lacking an internal limb.
The spores measure (8.5-) 10.1 - 12.8 (-15.0) × (6.5-) 7.0 -
9.8 (-10.9) µm and are inamyloid and broadly ellipsoid to ellipsoid
(infrequently subglobose, infrequently elongate, rarely
cylindric). Clamps are uncommon at bases of the basidia.
Amanita huijsmanii was originally described from France. It is known only from
F. Massart & Rouzeau. 1990 ["1989"]. Bull. Soc. Linn. Bordeaux 17(3): 159, pl. 1.
"Huijsman's Ringless Amanita"
≡Amanita argentea f. huijsmanii (F. Massart & Rouzeau) 1999. 1999. Boll. Acc. Gioen. Sci. Nat. 32: 20.
The editors of this site owe a great debt to Dr. Cornelis Bas
whose famous cigar box files of Amanita nomenclatural information
gathered over three or more decades were made available to RET for computerization
and make up the lion's share of the nomenclatural information presented on this site.
genitive of a Latinized name; hence "Huijsman's" or "of Huijsman"
composite of data from all material revised by RET: [80/3/3] (8.5-) 10.1 - 12.8 (-15.0) × (6.5-) 7.0 - 9.8 (-10.9) μm, (L = 11.3 - 11.5 μm; L' = 11.4 μm; W = 7.8 - 8.7 μm; W' = 8.4 μm; Q = (1.10-) 1.17 - 1.60 (-2.13); Q = 1.30 - 1.46; Q' = 1.36), hyaline, colorless, thin-walled, smooth, inamyloid, broadly ellipsoid to ellipsoid, occasionally subglobose, infrequently elongate, ocasionally adaxially flattened, occasionally expanded at one end; apiculus sublateral, cylindric; contents guttulate; white in deposit.
On right bank of Garonne R. in Entre-deux-mers, August and September, in deciduous or mixed woods, on clayey-calcareous soil.
DORDOGNE—Payzac, 17.x.1997 Christian Rouzeau s.n. [Massart 97058] (in herb. Massart; RET 272-7).
GIRONDE—St-Vivien-de-Monségur, 25.viii.1989 Francis Massart 89 A1/A2 (single collection in two packets) (holotype, in herb. Massart; isotype, RET 011-1, fragments), 17.vii.1997 Francis Massart 97043 (in herb. Massart; RET 272-8).
—R. E. Tulloss
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can be found here.
Each spore data set is intended to comprise a set of measurements from a single specimen made by a single observer;
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Combining more data into a single data set is non-optimal because it obscures observer differences
(which may be valuable for instructional purposes, for example) and may obscure instances in which
a single collection inadvertently contains a mixture of taxa.