Amanita westii has a pileus densely set with pyramidal warts
that are brown on the surface and white in the interior
(at least in young material). The basidiome is
prone to sordid reddish bruising and staining and has a
slight odor of anise. Dried specimens take on the
color of cocoa powder or a deep wine-red color somewhat
like that of dried specimens of Leucoagaricus americanus (Peck) Vellinga.
The cap of A. westii is 70 - 155 mm wide, convex to plano-convex, eventually
planar, subviscid to dry, pale reddish brown to pale
chocolate brown. The context is up to 20 mm thick above the stipe, white quickly bruising reddish brown or near
Prussian Red, then changing to Light Seal Brown, and eventually blackish; margin nonstriate, appendiculate
with material hanging down 3 - 4 mm; universal veil as large warts, pyramidal to somewhat flattened (in the
latter case often with a small central pimple), 2 - 4 mm high, with irregularly polygonal bases 3 - 5 × 8 - 10 mm,
largest near pileus margin, densest over disk, near Light Seal Brown, removable.
The gills are adnexed by a line to the stipe apex at first, then seceding, sometimes
remote at maturity, rather crowded to close to subdistant, white at first, then gray white, finally
reddish brown, drying reddish brown to dark brown, 10 - 12 mm broad; the short gills are brief, in one or two tiers,
with the shortest subtruncate to somewhat rounded subattenuate.
The stipe is 70 - 155 × 15 - 35 mm, more or less cylindric or constricted at
about the mid-point, covered at first with floccose-fibrillose material which adheres to the
fingers, densely floccose to floccose-subfelted in the
apical region below the annulus, becoming undecorated,
dry, originally whitish (sometimes becoming grayish) near
apex, otherwise reddish brown or a very dark brown or
pale reddish brown, concolorous with pileus in exsiccata;
context white, with color changes on cutting or bruising
as in the pileus, solid; the stipe's bulb is obovoid-napiform to napiform to turbinate to broadly
fusiform, radicating, occasionally abrupt to subabrupt,
up to 40 - 45+ × 30 - 50 mm, becoming colored
like other parts; the annulus is apical, subfelted to
felted-submembranous, fragile, detersile or adhering to
edges of lamellae, white at first, then pale reddish
brown, striate above, underside densely flocculose. The
volva consists of fibrillose material (occasionally vague
warts or felted patches) at the stipe base and on the
upper half of the stipe's bulb in the button stage, easily removed, colored as on pileus.
The odor is faintly of anise according to Murrill. The taste is sweet and
nutty at first, becoming slightly astringent according to Murrill.
The spores measure (8.5-) 10.5 - 13.9 (-15.5) × (5.0-) 6.0 - 7.8 (-8.2) µm and are
ellipsoid to elongate (occasionally cylindric) and
amyloid. Clamps are absent from bases of basidia
Amanita westii occurs in small groups in oak, oak-pine-beech, and oak-hickory forests.
The species is presently known only from Florida, Mississippi, and Texas, U.S.A. It should be expected
in appropriate habitats along the US coast of the Gulf of Mexico.
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.
Bas. 1969. Persoonia 5: 486, figs. 244-246.
Tulloss and Lewis. 1994. Mycotaxon 50: 131.
Tulloss and D. P. Lewis, here
The following text may make multiple use of each data field.
The field may contain magenta text presenting data from a type study
and/or revision of other original material cited in the protolog of the present taxon.
Macroscopic descriptions in magenta are a combination of data from the protolog and
additional observations made on the exiccata during revision of the cited original
The same field may also contain black text, which is data from a revision of the present
taxon (including non-type material and/or material not cited in the protolog).
Paragraphs of black text will be labeled if further subdivision of
this text is appropriate.
Olive text indicates a specimen that has not been
thoroughly examined (for example, for microscopic details) and marks other places in the text
where data is missing or uncertain.
The following material not directly from (Bas 1969) is based on original research by R. E. Tulloss and David P. Lewis.
70 - 155 mm wide (largest pileus measured not fully expanded), convex to plano-convex, eventually planar to plano-depressed, subviscid to dry, pale reddish brown (Murrill) to pale chocolate brown (Murrill), cracks between scales 10R 9/1 (near Pallid Vinaceous Drab), 10R 6/2 under warts, drying dark wine color reminiscent of dried basidiomes of Leucoagaricus americanus; context 10 - 20 mm thick over stipe, white quickly bruising reddish brown or 7.5R 4/4 (near Prussian Red) changing to 10R 2/2 (near Light Seal Brown), eventually blackish, the color of cocoa powder in exsiccata; margin nonstriate, appendiculate with material hanging down 3 - 4 mm; universal veil as large warts, pyramidal to somewhat flattened (in latter case often with small central pimple), 2 - 4 mm high, with irregularly polygonal bases 3 - 5 × 8 - 10 mm, largest near pileus margin, densest over disk, 10R 2/2 (near Light Seal Brown), detersile.
adnexed by a line to stipe apex at first, then seceding, sometimes remote at maturity, rather crowded to close to subdistant, white at first, then gray white, finally reddish brown or 10R 6/2, drying reddish brown to dark brown, 10 - 12 mm broad, with edge thick and flocculose to fimbriate to almost crenate; lamellulae short, in one or two tiers, with the shortest subtruncate to somewhat rounded subattenuate, with the longest not distinguishable in exsiccata (notes from fresh material lacking).
70 - 155 × 15 - 35 mm, more or less cylindric or constricted at about mid-height, covered at first with floccose-fibrillose material which adheres to fingers, densely floccose to floccose-subfelted in apical region below partial veil, becoming undecorated, dry, originally whitish (sometimes becoming grayish) near apex, otherwise reddish brown or very dark brown or pale reddish brown or 10R 6/2, concolorous with pileus in exsiccata; context white, with color changes on cutting or bruising as in pileus, solid; bulb obovoid-napiform to napiform to turbinate to broadly fusiform, radicating, occasionally abrupt to subabrupt, up to 40 - 45+ × 30 - 50 mm, becoming colored like other parts; partial veil apical, subfelted to felted-submembranous, fragile, detersile or adhering to edges of lamellae, white at first, then pale reddish brown or 10R 6/2, striate above, underside densely flocculose; universal veil as fibrillose material (occasionally vague warts or felted patches) at stipe base and on upper half of bulb in “button” stage, detersile, colored as on pileus.
Odor faintly of anise (Murrill). Taste sweet and nutty at first, becoming slightly astringent (Murrill).
In mature material: 50 - 65 µm thick, orange-brown in 3% KOH, with surface extensively gelatinized and depigmented; filamentous, undifferentiated hyphae 1.0 - 9.8 µm wide, subradially oriented, tightly interwoven, branching; vascular hyphae 5.0 - 17.5 µm wide, branching, most easily seen in scalp. In "button": 45 - 60 µm thick, ungelatinized, orange-brown to yellow-brown in 3% KOH.
cell walls hyaline to yellow-brown to orange-brown in 3% KOH, with those having thickest walls among (but not exclusively) the most strongly pigmented; filamentous, undifferentiated hyphae 2.2 - 9.2 µm wide, branching, often in fascicles, with some intercalary segments inflated up to 15.0 µm wide (cylindric), with walls thin or up to 0.8 µm thick, with septa often constricted; acrophysalides dominating, narrowly fusiform to clavate to broadly clavate to ovoid to ellipsoid, up to 124 × 68 µm, with walls thin or up to 0.8 µm thick; vascular hyphae not observed; clamps not observed.
bilateral, with shallow to very shallow angle of divergence, poorly rehydrating in some sections from the holotype, with wcs = 50 - 65 µm; filamentous, undifferentiated hyphae 1.8 - 9.2 µm wide, branching, densely interwoven, with some intercalary segments slightly inflated; divergent, terminal, inflated cells not observed; vascular hyphae not observed.
inflated ramose to ramose, with depth of subhymenial tree 10± µm under longest basidia/-oles and 25± µm under shortest basidioles, comprised of uninflated or partially inflated short hyphal segments (up to about 16 µm long, but most shorter than 13 µm long) in branching structure, sometimes with ovoid to ellipsoid intercalary inflated cells (these larger than most uninflated hyphal segments and concentrated adjacent to central stratum), rather densely interwoven, with basidia arising from both ends and sides of hyphal segments, with some segments parallel to the central stratum immediately below the bases of the longest basidia, with about one to three cells between divergence from central stratum and base of basidium.
[Note: This description should be re-checked in fresher material, it may be influenced misinterpretation by RET of poorly rehydratd tissue.—RET]
41 - 64 (-70) × (7.2-) 9.0 - 13.2 (-14.0) µm, dominantly 4-, but occasionally 2- or 1-sterigmate, many with yellowish brown to pale yellowish brown contents in side view (orange-brown to red-brown in mass or in end view) in both 3% KOH and 2-3% NH4OH, sometimes orange-brown to red-brown in Melzer’s Reagent; clamps not observed.
On pileus (from “button”): elements with vertical orientation except near base, there often with periclinal orientation, frequently hyaline or pale yellow, occasionally orange-brown (but then for only a few consecutive hyphal segments or even only for a portion of one segment), less pigmented than adjacent pileipellis and pileus context; filamentous, undifferentiated hyphae 3.2 - 15.0 (-26) µm wide, branching, with walls thin or slightly thickened, some with pale yellow walls, plentiful to dominating in the base of the wart, otherwise scattered; inflated cells terminal, singly or in chains, broadly fusiform to clavate to ovoid to ellipsoid to subglobose, with the roundest nearest top of wart, dominating above base of wart, up to 112 × 64 µm or larger, with walls usually at least somewhat thickened (up to 0.8 µm thick); vascular hyphae 4.5 - 12.0 µm wide, yellow-brown, absent in most sections, relatively common in one, frequently branching; clamps not observed. On stipe base: similar.
longitudinally acrophysalidic, with cell walls hyaline to brown; filamentous, undifferentiated hyphae 1.5 - 10.5 µm wide, branching, often in fascicles, plentiful, with walls thin or up to 1.0 µm thick, with some intercalary cells having form and size of acrophysalides; acrophysalides plentiful, up to 211 × 51 µm, with walls thin or up to 1.0 µm thick; vascular hyphae 4.0 - 21 µm wide, branching, yellow-brown, common.
cells hyaline to yellow-walled to brown-walled; filamentous, undifferentiated hyphae 2.0 - 10.5 µm wide, in tangled and interwoven fascicles, branching, with majority subradially oriented, many collapsed or poorly rehydrating, plentiful to locally dominant, with many terminal segments slightly inflated, with some intercalary segments slightly inflated (cylindric), thin-walled or with walls slightly thickened; inflated cells fusiform to narrowly fusiform to narrowly ellipsoid to subclavate, with narrower forms often subrostrate to rostrate, up to 125 × 32 µm, terminal, singly, with walls thin or up to 0.8 µm thick; vascular hyphae not observed.
lamella edge tissue
Bas (1969): [20/1/1] 11.5 - 14.5 × 7.0 - 8.0 μm, (Q = 1.6 - 2.0; Q = 1.7 - 1.8), thin-walled, smooth, amyloid, elongate to elongate-pyriform, often with somewhat "sagging base"; apiculus often sublateral to lateral; contents granular, brownish-yellowish "turning reddish brown in Melzer's Reagent and then more or less screening amyloid reaction of wall (Bas 1969: 485: fig. 245).
from type study of Jenkins (1979): [-/-/1] 12.5 - 13.3 (-14.1) × 7.0 - 8.6 μm, (Q = 1.45 - 2.00; Q' = 1.76),
hyaline, thin-walled, amyloid, ellipsoid to cylindric, often adaxially flattened; apiculus sublateral, cylindric; contents guttulate;
color in deposit not recorded.
Composite of data from all material examined by RET: [140/6/4] (8.5-) 10.5 - 13.9 (-15.5) × (5.0-) 6.0 - 7.8 (-8.2) µm; L = 11.0 - 12.8 µm; L' = 12.2 µm; W = 6.6 - 7.3 µm; W' = 6.9 µm; Q = (1.42-) 1.53 - 2.0 (-2.18); Q = 1.67 - 1.87; Q' = 1.77), hyaline, smooth, thin-walled, amyloid, ellipsoid to elongate, often adaxially flattened, often slightly swollen at one end, often constricted; apiculus sublateral, small, truncate-conic to cylindric; contents granular, in holotype sometimes yellowish brown in dilute basic solution and turning reddish brown in Melzer’s Reagent and then [per Bas (1969)] sometimes masking amyloid reaction; color in deposit unknown.
Solitary to subgregarious. Florida: under Quercus in dry, high hammock (a term peculiar to Florida and indicating usually mesic, climax vegetation—hardwood forest including Quercus, Magnolia, etc.—often slightly elevated compared to surrounding terrain). Mississippi: in a mesic forest of Pinus, Quercus, and Fagus near a large creek. Texas: in a xeric forest largely of Quercus and Carya or under Quercus stellata on sandhill.
Bas (1969): U.S.A.: FLORIDA—Alachua Co. - east of Gainesville, Newmann’s Lake, 7.vii.1938 E. West s.n. (holotype, FLAS F17466).
from type study of Jenkins (1979): U. S. A.: FLORIDA— Alachua Co. - Newman's Lake near Gainesville,
7.vii.1938 Erdman West F. 17466 (holoype, FLAS).
FLORIDA—Alachua Co. - east of Gainesville, Newmann’s Lake, 7.vii.1938 E. West s.n. (holotype, FLAS F17466).
MISSISSIPPI—Perry Co. - DeSoto National Forest, Cypress Creek Landing, 29.vi.1991 Toby Feibelman 1165 (F; L; RET 046-8).
TEXAS—Newton Co. - Lewis Chapel community, Sand Ridge Cemetery, 19.vii.2007 Bart Buyck & Benj. Wolfe & D. P. Lewis [Buyck 07-015 ; Lewis 8117; Wolfe BW_SH26] (F; FH; PC; RET 414-3); Scrapping Valley Timber and Wildlife Research Area, off State Hwy. 87 and Recreational Rd. 255 [31°06.730' N/ 93°47.492' W], 1.viii.1987 D. P. Lewis & J. Parigi [Lewis 4074] (F; RET 042-7).
The large, dark, pyramidal warts and reddish staining reaction of the context make A. westii a striking species. It is unique in color and habit among the taxa of Amanita described from the Western Hemisphere. The universal veil decorating the pileus often takes on such a strikingly spiky form that, from a distance, one may mistake a specimen of A. westii for a bolete belonging in the genus Strobilomyces B. Examination of the universal veil on recently collected material (including “button” specimens) supports the likelihood observed by Bas (1969; pers. comm.) that this North American entity has as its closest known phyletic relative A. sculpta Corner & Bas (1962) described from North Borneo and Singapore.
In both 3% KOH and 2-3% NH4OH, the color of spore contents was not as strong as observed by Bas (1969), but, instead, like the yellow of most refractive cell contents seen in amanitas. The reddish-brown tint of spore contents observed in Melzer’s Reagent was visible despite the strong amyloid reaction of the spore wall (observed at 1000×). However, the reddening of contents was never seen to occur so completely or intensely as to mask the amyloid reaction as was noted by Bas. Bas noted scattered brown vascular hyphae in the universal veil warts on the pileus; such hyphae were found in only one of numerous sections of warts from recently collected material.
The stipe context of A. westii is curious in that many of the apparent acrophysalides are seen to be intercalary cells with uninflated hyphal segments connected at both their broad and narrow ends.
—R. E. Tulloss and D. P. Lewis
Information to support the viewer in reading the content of "technical" tabs
can be found here.
1. Amanita westii, Mississippi.
2. Amanita westii, eastern Texas, U.S.A.
3. Amanita westii, eastern Texas, U.S.A.
4. Amanita westii, eastern Texas, U.S.A.
5. Amanita westii, eastern Texas, U.S.A.
Dr. Toby Feibelman - (1) Mississippi, U.S.A.
David P. Lewis - (2-3, 5) eastern Texas, U.S.A.
Benjamin Wolfe - (4) eastern Texas, U.S.A.
Each spore data set is intended to comprise a set of measurements from a single specimen made by a single observer;
and explanations prepared for this site talk about specimen-observer pairs associated with each data set.
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.