The cap of Amanita agglutinata is up to 40 mm wide, globose at first, finally plano-convex, viscid, pallid, pale yellow, nonappendiculate, and with a short striate margin. The volval remnants are off-white, rather prominent chunky warts that are easily removed when the cap is moist.
Gills are crowded, free, white, broad,
ventricose, and rounded near the stipe; the short gills are truncate.
Its stem is 10 - 35 × 3 - 7 mm, tapering
slightly upward, slightly expanded at the top of the stem, stuffed,
and with a subfibrillose surface. The volva is appressed against the base of the stem.
The spores measure 8.5 - 11 (-14.8) × (5.5-) 6.0 - 7.2 (-7.5) µm and are ellipsoid to
elongate and are inamyloid. The basidia lack clamps at their bases.
I have found this species only once and have merged the description with Jenkins'' description of the type collection. The species is known from the southeastern U.S. Apparently, it is rare or is rarely recognized. The single collection of mine was made in an open forest with plentiful oaks.
Descriptions of various mycologists that place the present species in section Amidella are in error because of the inamyloid spores of A. agglutinata. Those who would place this species in section Vaginatae are in error because of the presence of a bulb at the stipe base.—R. E. Tulloss
≡Agaricus agglutinatus Berk. & M. A. Curtis in Berk. 1849. Hooker's London J. Bot. Kew Gard. Misc. 1: 97-98.
≡Amanitopsis agglutinata (Berk. & M. A. Curtis) Sacc. 1887. Syll. Fung. 5: 23.
≡Vaginata agglutinata (Berk. & M. A. Curtis) Kuntze. 1898. Rev. Gen. Plant. 3: 539.
[Several times misapplied to Amanita volvata (Peck) Lloyd.]
[Misapplied to unknown species of Amanita section Vaginatae by Pegler (1978. Kew Bull., Addit. Ser. 9: 290).]
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.
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 the protolog of the present taxon and not cited as the work
of another researcher is based on original research of R. E. Tulloss.
from type study of Jenkins (1977): [-/-/1] 9.0 - 12.5 × 5.5 - 8.0 μm, (Q = 1.40 - 1.90; Q' = 1.62), hyaline, colorless, smooth, thin-walled, inamyloid, ellipsoid to elongate, adaxially flattened; apiculus eral, cylindric to truncate-conic, up to 2.5 μm long; contents guttulate to subgranular; color in deposit not reported.
Subgregarious. Kentucky: In loamy soil, under species of Quercus including Quercus alba and Q. stellata.
from type study of Jenkins (1977): U.S.A.:
SOUTH CAROLINA— Unkn. Co. - unkn. loc., vii.1847 M. A. Curtis 1322 (holotype, K).
KENTUCKY—Laurel Co. - Levi Jackson Wilderness Trail St. Pk., 20.vii.1987 D. C. Tulloss s.n. [R. E. Tulloss 7-20-87-C] (RET 005-3).
In the following figure, the sporographs of a group of macroscopically similar collections that have temporary names are compared with the spore size and shape data of the present species. The temporary names involved are A. sp-N08, A. sp-N19, and A. sp-S01.
—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.