For the moment, please see the technical tab of this page.
The odor of this species is faint to lacking. The taste has not been recorded.
This species can have a largely or entirely white cap, but
is molecularly distinct from A. rubescens
var. alba. Moreover, the present species
sometimes has a distinctly yellow volva that can be
left in part on the underside of the stem's
This species was formerly called "Amanita
sp-amerirubescens01" on the present site.—R. E. Tulloss
Tulloss and K. W. Hughes
"Golden Underskirt Blusher"
Due to delays in data processing at GenBank, some accession numbers may lead to unreleased (pending) pages.
These pages will eventually be made live, so try again later.
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 original research of R. E. Tulloss.
51 - 128 mm wide, whitish to cream to pale tan at first, bruising or staining pinkish to pale red-brown to pale brown to red-brown, sometimes appearing radially fibrillose, subovoid at first, then convex to planoconvex, sometimes depressed in disc, tacky, subshiny to shiny when dry; context white, bruising brick red to wine-brown, 4 - 9.5 mm thick over stipe, thinning evenly to margin; margin nonstriate or very short-striate to pronouncedly striate in age, nonappendiculate, decurved; universal veil yellow to cream at first, staining/bruising beige to red-brown, with tips often darkening first, detersile at first, at times becoming adnate, subpyramidal, verruculose, with irregularly polygonal base.
free to narrowly adnate with decurrent tooth and descending line on upper stipe, subcrowded to crowded, white to pale cream to faintly sordid cream in mass, white to whitish to very pale cream in side view, bruising as in pileus context, up to 5.5 - 10 mm broad, of constant breadth for most of length, sometimes forking, sometimes anastomosing; lamellulae subtruncate to rounded truncate to subattenuate to attenuate to attenuate in steps, ??.
35 - 65 × 8 - 16 mm, white at first, becoming almost entirely reddish brown to wine-brown to brownish, narrowing upward (rarely narrowest at mid-stipe), flaring at apex, finely pulverulent above, finely longitudinally striatulate; bulb up to 26 - 38 × 16 - 27 mm, broadly fusiform; context stuffed, white, staining brick-red to wine-red, with firm white stuffing material extending into upper third of bulb, with central cylinder ca. 4 mm wide, with larval tunnels concolorous with other bruised/stained parts of context; partial veil subapical to superior, membranous, skirt-like, eventually collapsing on stipe, striate above, floccose-fibrillose below, white to pale sulfur yellow to sulfur yellow above and white to sulfur yellow to more intensely yellow below, staining as in remainder of basidiome; universal veil often not evident at stipe base.
RET: [95/3/3] (7.0-) 7.5 - 10.0 (-11.2) × (4.9-) 5.5
- 7.0 (-8.3) μm, (L = 8.4- 9.2 μm; L' =
8.7 μm; W = 5.9 - 6.3 μm; W' = 6.1 μm;
Q = (1.19-) 1.27 - 1.65 (-1.69); Q = 1.32 -
1.52; Q' = 1.43), hyaline, colorless,
thin-walled, smooth, amyloid, broadly ellipsoid to
ellipsoid, infrequently elongate, adaxially
flattened; apiculus sublateral, cylindric,
proportionately small; contents granular to
mono- or multiguttulate with or without additional
small granules; white in deposit.
Missouri: In Quercus dominated forest. South Carolina: In duff under woodchips in landscaped (watered) area during drought under Q. alba, Rhododendron, and Ilex opaca or in dark loamy soil of reforested abandoned farm yard with Pinus echinata, Q. rubra, Q. alba, Q. bicolor(?), Q. marilandica, Carya sp., Prunus sp., Cornus florida, and Toxicodendron radicans.
CONNECTICUT—Unkn. Co. - Salmon River St.
Pk., 4.ix.2011 Sandy Sheine s.n. [Tulloss 9-4-11-J]
(RET 488-2, nrITS & nrLSU seq'd.).
ILLINOIS—Clark Co. - Lincoln Trail
St. Pk. [39.335° N/ 87.715° W, 163 m], 25.viii.2014
P. Harvey s.n. [mushroomobserver
(RET 638-8, nrITS & nrLSU seq'd.).
INDIANA—Monroe Co. - SE of Bloomington,
Lake Monroe, Paynetown St. Recreation Area
[39.0941° N/ 86.4476° W, 174 m], 1.ix.2012 Stephen
Russell 3842 [mushroomobserver #108032]
(RET 530-10, nrITS seq'd.). Montgomery Co. -
Waveland, Shades St. Pk. [39.9378° N/ 87.0894° W,
223 m], 28.viii.2012 S. Russell 3617
(RET 530-4, nrITS & nrLSU seq'd.).
MISSOURI—Jasper Co. - NW of Kendricktown
[37.2062° N/ 94.3354°W, 311m], 14.vi.2013 Jon
Shaffer s.n. [mushroomobserver #136364]
(RET 547-9, nrITS & nrLSU seq'd.), 6.viii.2013
J. Shaffer s.n. [mushroomobserver #141950]
(RET 564-7, nrITS & nrLSU seq'd.).
Jefferson Co. - Cliff Cave Park, Cliff Cave,
8.ix.2009 Patrick Harvey s.n. [mushroomobserver
(RET 443-6, nrITS & nrLSU seq'd.).
Newton Co. - Neosho,
Fort Crowder Conservation Area [36.8167° N/
94.3061° W, 370m], 14.viii.2013 J. Shaffer s.n.
(RET 564-4, nrITS & nrLSU seq'd.).
NEW JERSEY—Mercer Co.
- Hopewell, off Carter Rd., woods behind
AT&T/Lucent research labs [40°21’39” N/
74°43’29” W, 63 m], 19.vii.1984 R. E. Tulloss &
C. D. Hechtman [Tulloss 7-19-84-C] (RET
Warren Co. - Yards Creek Scout
Reservation, NW of Blairstown, 5.vii.1981 Mary A.
King & Mark. H. & R. E. Tulloss 7-5-81-B
NORTH CAROLINA—McDowell Co. -
Little Switzerland, Blue Ridge Mtns., Wildacres
Retreat, 15.ix.2014 W.S. s.n. [mushroomobserver
(RET 647-9, nrITS & nrLSU seq'd.).
SOUTH CAROLINA—Oconee Co. - Seneca,
28.vi.1985 R. E. Tulloss 6-28-85-C (RET 055-4,
nrITS & nrLSU seq'd.), 18.vii.1986 M.A. King,
D.C. & R.E. Tulloss 7-19-86-B (RET 079-5,
- McLean, 3.viii.1992 Buck McAdoo 207#15 (RET
Despite the sometimes white or very pallid pileus,
this species often can be segregated in the field
from the material determined on this site as
rubescens var. alba. The
present species often has a yellow partial
veil. The yellow universal veil material
(illustrated on this page as it appears on the
underside of the partial veil) and the pale sulfur
yellow to sulfur yellow upper surface of the partial
veil is not seen in A. rubescens var.
In the following figure, sporographs for the
present species and A. rubescens var.
alba are compared:
The presently known range of this taxon extends
from Connecticut to South Carolina in the eastern
U.S. and, thence, westward to Indiana and
The taxa with temporary code names of the form
"sp-amerirubescnes0X" (where "X" is an integer) were
originally treated on this site as a single taxon
amerirubescens." The latter taxon
page is maintained on the site and references
collections still not divided among the temporary
The present species formerly bore the temporary code
—R. E. Tulloss
Information to support the viewer in reading the content of "technical" tabs
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;
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.