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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).
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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 is derived from molecular
studies of Dr. Linas Kudzma and other original
research of RET.
yellowish tan at first then orangish-tan, in both
cases with darker brown band over inner part of
marginal striations, ??;
margin striate (0.2 - 0.25R), nonappendiculate;
??; universal veil at
least sometimes with white membranous volval fragments
concentrated over disc.
1-, 2-, and 4- sterigmate in immature
material; clamps not observed.
[8/1/1] 11.5 - 14.0 (-15.1) × 10.3 - 12.7 (-13.9) μm,
(L = 12.7 μm; L' = 12.7 μm; W
= 11.6 μm; W' = 11.6 μm;
Q = (1.03-) 1.09 - 1.14; Q = 1.09; Q'
hyaline, colorless, smooth, thin-walled, inamyloid,
subglobose (infrequently globose), at least somewhat
flattened adaxially, with giant spores
present in immature material;
apiculus sublateral, cylindric to
truncate-conic, proprotionately large;
contents ??; ?? in deposit. [Note: the
single specimen reviewed is immature with very few
sterigmate basidia. The largest recorded
spores are likely to have come from basidia bearing
less than four spores.—ed.]
Arizona: At 3186 m elev. In dark soil (staining the
stem base of the exsiccatum), with Pseudotsuga
California: Solitary. At 670 m elev.
Along road in forest dominated by Pseudotsuga
ARIZONA—Graham Co. - Mt. Graham, near
observatory [32.7018° N/ 109.8900 W, 3186 m],
8.ix.1986 Jack S. States AEF429 (MICH,
on extended loan to RET, nrITS & nrLSU seq'd.).
CALIFORNIA—Shasta Co. - Castella
[41.1399° N / 122.315° W, 670 m],
8.ix.2013 Aron Cena 2013090801 [mushroomobserver
(RET 660-4, nrITS & nrLSU seq'd.),
12.x.2013 A. Cena 2013101203 [mushroomobserver
(RET 660-9, nrITS & nrLSU seq'd.), 13.x. 2013
A. Cena 2014112201 [mushroomobserver
(RET 664-8, nrLSU seq'd.)
22.xi.2014 David Kent 1013133 [mushroomobserver
(RET 660-8, nrITS & nrLSU seq'd.).
WASHINGTON—Whatcom Co. - Mt. Baker,
Hannegan Pass Tr., 27.x.1991 Buck McAdoo 117#3 (RET
049-8, nrITS-LSU seq'd.).
In the single specimen shared with me by Dr. States,
the base of the stipe
and the volva are lost.
Dr. States' notes record "cf. A.
umbrinolutea." This suggests a zonate
distribution of pigment on the pileus (involving
three or more concentric zones); however,
such pigmentation is
not clearly evident in the exsiccatum.
This species probably has the unusual nrLSU 5' motif that is
associated with series Penetratrices.
A list of species having the same motif is
available on the
techtab of A.
A recent single gene (nrLSU) tree showed the present
species in a small cluster including two other
emodotrygon. The latter (described
from northern India) has a brownish gray band
over the marginal striations on an otherwise a
pale gray cap (i.e., two color zones). The
former is pale gray with some yellowish
tint over the disc.
States AEF429 had not achieved maturity; very
few basidia bear sterigmata.
We were not successful in deriving an nrITS sequence
from this species. However, we did succeed in
obtaining 200 characters from the 3' end of 18S and
much of ITS1 and a similar sized fragment including
the 3' end of ITS2 and dominated by a 28S fragment
including the 5' motif known from the "series
This species has been identified several times by
experienced collectors as a pallid or "albino" form of
Amanita pachycolea. Presumably this
is because of the dark ring over the inner ends of
the marginal striations.
On this site, this taxon has formerly been called
—R. E. Tulloss & L. V. Kudzma
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