Amanita velosa has a cap 42 - 110 mm wide that is pale
yellowish orange to pale orangish beige to pale orange or bittersweet orange to orange or yellowish orange to
brownish orange with darker or paler streaks (possibly
due to action of rain), sometimes becoming paler (e.g.,
pale orange to cream) toward margin. The pigment is
sometimes washed out entirely by heavy rain. Occasionally, an
entirely white specimen is found. The fleshy
cap lacks an umbo or has a low, broad one and often bears
one or more white membranous patches of volva. The
marginal striations of the cap are short—usually having length of about 10% to 20% of the cap radius.
The gills are free to narrowly adnate, crowded, off-white to pale cream to pale orangish
cream in mass, 4 - 10.5 mm broad, with some reverse
forking and anastomosing present; the short gills are
more or less truncate, plentiful, unevenly distributed,
of diverse lengths, occasionally adjacent to the stipe as well as to the margin.
The stem is 76 - 133 × 9 - 26 mm white to pale orange-white above, white below, and
exannulate; it bears a robust, white, membranous, sack-like volva.
The odor of this species is variously reporated as lacking to faintly fungoid to faintly fishy to faintly sweet. The taste is said to be faintly sweet and slightly nut-like, or very pleasant by Californians who enjoy eating A. velosa.
The spores measure (8.7-) 9.1 - 12.0 (-16.3) × (7.0-) 7.7 - 10.0 (-13.0) µm and
are subglobose to broadly ellipsoid (infrequently globose
or ellipsoid) and inamyloid. Clamps are not present at bases of basidia.
Amanita velosa occurs with oak.
The species is known from Oregon and California, U.S.A. and from the Baja California Peninsula, Mexico.
Nearly white specimens have been misdetermined as a European species, A. vaginata
var. alba Gillet (sometimes mistakenly called "Amanita alba," which is an old [not
currently accepted] name for a European species of Amanita sect, Amidella). Based on available evidence, A.
vaginata var. alba does not occur in the Western Hemisphere.—R. E. Tulloss
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.
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 is based on the personal research of R. E. Tulloss.
42 - 110 mm wide, pale yellowish orange (4A3) to pale orangish beige (a little darker than 4A3) to pale orange or bittersweet orange (5A4-5 to a little paler than 5A4) to orange (5A5) to brownish orange with darker or paler streaks (7.5YR 8/4-6 or 7.5YR 5-7/8) possibly due to action of rain, sometimes becoming paler (e.g., pale orange to cream) toward margin, with pigment often entirely washed out by heavy rain, at first ovoid, then hemispheric to convex, then planoconvex and developing low broad umbo, shiny to subshiny to dull, viscid to subviscid when wet, otherwise faintly tacky or appearing waxy, sometimes pruinose under universal veil patch; context white, sometimes pinkish orange under pileipellis, somewhat sordid or pale brownish white in disc in age, unchanging when bruised or cut, 4 - 15 mm thick at stipe, usually thinning evenly for about 80 - 90% or more of R, then membranous to margin, occasionally thinning evenly from stipe to margin, not easily separated from stipe context; margin striate [(0.5-) 0.1 - 0.2 (-0.3)R], nonappendiculate, downcurved at first, flaring upward in age; universal veil as membranous patch or patches, white, unchanging when cut or bruised, sometimes becoming sordid or slightly brownish when watersoaked or approaching senescence, scruffy/cottony at first, drying to leathery, sometimes becoming areolate, detersile.
free to narrowly adnate with long but faint decurrent line on stipe apex, sometimes receding, crowded, off-white to pale cream to pale orangish cream in mass, white to off-white to pale cream in side view, unchanging when cut or bruised, 4 - 10.5 mm broad, with white to pale orange flocculose margin (lens), some reverse forking and anastomosing present; lamellae truncate to excavate-truncate to subtruncate, plentiful, unevenly distributed, of diverse lengths, occasionally originating at stipe as well as at margin.
76 - 133 × 9 - 26 mm, white to pale orange-white above, white below, sometimes becoming sordid from handling, with surface fibrils browning from handling, subcylindric to cylindric pr narrowing upward, occasionally flaring at apex, with obconic base, base of stipe often slightly dog-legged, faintly to distinctly pulverulent above (some times extending downward to median region), longitudinally striate and fibrillose in lower three-quarters, with fibrils often rather densely placed and forming upward pointing squamules; context white to off-white to pale cream, occasionally watersoaked/sordid near base, sometimes with orangish brown spot below central cylinder, not changing when cut or bruised, stuffed firmly with white material that may be firmer than surrounding context, sometimes becoming partially hollow, with central cylinder 2 - 15 mm wide; exannulate; universal veil as saccate volva, white on exterior and in interior, palely concolorous with pileus for upper 25 - 50% of limb and whitish below on the inner surface, with limb margin sometimes becoming brownish with age or drying, soft, membranous, persistent, rather tough, sometimes leathery, 1- - 2+ mm thick at midpoint between top of limb and attachment to stipe, 26 - 70 × 28- - 46 mm (length measured from stipe base to highest point of limb) and adnate to stipe for two-thirds or more of this distance, with small limbus internus at point of attachment to stipe.
Odor lacking to faintly fungoid to faintly fishy to faintly sweet. Taste faintly sweet and slightly nut-like, very pleasant.
Spot test for tyrosinase (paracresol) - positive (deep wine color) throughout basidiome (although sometimes slowly for some areas on lamellae) in < 3 min. Spot test for laccase (syringaldazine) - immediately positive (fading after less than half a minute) in lower volva, then positive (after 4 min) in small spot on stipe surface near top of volval limb or in dot in interior at base of central cylinder. Results according to Breckon (1968)—on exposed context of the lower stipe and bulb unless otherwise noted: FeSO4 - yellow. 15% KOH, concentrated KOH, Melzer’s Reagent - negative. Phenol, phenolaniline - positive. Tincture of guaiac - positive, at times slowly so. Test voucher: Tulloss 2-14-98-C.
from type study of Jenkins (1978a): [-/-/1]
9.4 - 10.9 × 7.8 - 9.4 μm, (Q = 1.09 - 1.27; Q' = 1.16),
hyaline, thin-walled, nonamyloid, subglobose to broadly ellipsoid, often adaxially flattened; apiculus sublateral, ctruncate-conic; contents guttulate;
color in deposit not recorded.
[70/3/3] (8.7-) 9.1 - 12.0 (-16.3) × (7.0-) 7.7 - 10.0 (-13.0) µm, (L = 9.7 - 11.0 µm; L’ = 10.4 µm; W = 8.5 - 9.1 µm; W’ = 8.8 µm; Q = (1.04-) 1.08 - 1.30 (-1.49); Q = 1.15 - 1.24; Q’ = 1.19), hyaline, colorless, thin-walled, smooth, inamyloid, subglobose to broadly ellipsoid, occasionally globose, adaxially flattened, often expanded at one end, infrequently strangulate-elongate; apiculus sublateral, cylindric to narrowly truncate-conic; contents dominantly monoguttulate; white in deposit.
Solitary to gregarious. California: From near sea level up to 600 m elev. In loose duff, loam, or sandy loam, associated with Quercus (especially Q. agrifolia) or in Pinus-Quercus-Manzanita woodland. Oregon: Under solitary Q. garryana in lawn.
from type study of Jenkins
U. S. A.:
CALIFORNIA—Los Angeles Co. - Pasadena,
1895 A. J. McClatchie s.n.
MÉXICO: BAJA CALIFORNIA DEL
NORTE—15 km NW of Ensenada, El Junco,
iii.1983 Ayala 35 (RET 121-9; XAL n.v.).
Co. - Oakland, Lk. Chabot, 3.ii.2003 D. Viess s.n.
(RET 367-1). El Dorado Co. - Cool,
14.iv.2001 D. Viess s.n. (RET 327-3; in herb. D.
Viess). Los Angeles Co.
- Santa Monica Mtns., Cold Crk. Cyn. Preserve,
Stunt Cyn., 25.ii.1989 Eva Morgan s.n. [Tulloss
2-25-89-A] (RET 040-7), 25.ii.1989 Steven Pencall
s.n. [Tulloss 2-25-89-C] (RET 041-3).
Monterey Co. - Fort Ord, 14.ii.1998 Ronald
Pastorino s.n. [Tulloss 2-14-98-C]
(RET 275-1). Santa Cruz Co. - Aptos Hills,
S border of Aptos, 2.iii.1989 John Feci & R. E.
Tulloss 3-2-89-A (RET 040-6); Aptos Hills, N
border of Watsonville, 3.iii.1989 J. Feci s.n.
[Tulloss 3-3-89-A] (RET 040-5). Sonoma Co. -
Shiloh Ranch Reg. Pk., 20.ii.1998 S. Davidson, M.
Handler, P. Peterson, D. C. & R. E. Tulloss
2-20-98-A (RET 274-1).
OREGON—Douglas Co. - Umpqua, 1049
Joelson Rd., 10.iv.1995 Jack Hausotter s.n. [J. E.
Lindgren 96-04] (JEL n.v.; NY; RET 276-4).
[NOTE: See Sundberg 357
—R. E. Tulloss
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