The following is based on the original description of Murrill (1945), with the addition of my observations on the type. RET would like to make it clear at the outset that this species is very difficult to separate from A. elliptosperma. The possibility of synonymy is very real.
The cap of Amanita verniformis is 70 mm wide, convex to plane, solitary, slightly viscid, smooth, glabrous, milk-white, with an entire even margin. The flesh is thin, white, and unchanging.
The gills are just touching, close, narrow, inserted, white, with fimbriate edges.
The stem is 80 × 10 mm, subcylindric above the bulb, smooth, white, unchanging, glabrous. The bulb is large, ovoid, and white. The volva is limbate with ample limb and white. The ring is ample, white, and fixed 10 mm from the top of the stem.
As a precaution this species should be considered deadly POISONOUS.
The spores of the type measure (9.0-) 9.2 - 11.2 (-11.8) × 6.5 - 8.2 µm and are broadly ellipsoid to ellipsoid to (occasionally) elongate and amyloid. Clamps are absent from bases of basidia.
This species was originally described from Florida, where it was found under live oak.
In this original description, Murrill fails to compare A. verniformis to his previously described species, focusing only on the supposed similarity to A. verna (Bull. : Fr.) Lam. It seems possible that in creating A. verniformis he was redescribing material that could have been determined under his previous name, A. pseudoverna.
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 Dr. Z. L. Yang or another researcher is based upon original research by R. E. Tulloss.
small, white, convex; context not described; margin very slightly striate; universal veil not mentioned.
from type study of Jenkins (1979): [-/-/1] (9.4-) 10.2 - 10.9 (-11.7) × 7.0 - 7.8 (-8.6) μm, (Q = 1.12 - 1.56; Q' = 1.37),
hyaline, thin-walled, amyloid, ? to ?, often adaxially flattened; apiculus sublateral, short,truncate-conic; contents guttulate;
color in deposit not recorded.
RET study of type: [40/1/1] (9.0-) 9.2 - 11.2 (-11.8) × 6.5 - 8.2 μm, (L = 10.3 μm; W = 7.5 μm; Q = (1.22-) 1.24 - 1.60 (-1.69); Q = 1.37), hyaline, colorless, smooth, thin-walled, amyloid,broadly ellipsoid to ellipsoid, infrequently elongate, at least somewhat adaxially flattened; apiculus sublateral, cylindric to truncate-conic; contents guttulate to granular; ?? in deposit.
Florida: "near live-oak + pine."
from type study of Jenkins (1979):
U. S. A.: FLORIDA— Alachua Co. - Newman's Lake, 9.vii.1944 W. A. Murrill F 32931 (holotype, FLAS).
U. S. A.: FLORIDA—Alachua Co. - E of Gainesville, W of Newman's Lk., Weber's Pond, 9.vii.1944 W. A. Murrill s.n. (holotype, FLAS F32931).
Sporographs are provided to compare spore size and shape similarity with the relatively well known taxa A. magnivelaris (green figure) and A. elliptosperma (orange figure).
—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.