2. Amanita verna, showing reaction to KOH solution, southwestern France.
The following is largely based on the description of Neville and Poumarat (2004).
The cap of Amanita verna is 45 - 65 mm wide, white, yellow-ochre in the center, at first hemispheric with a flattened center, then convex, finally nearly planar, smooth, shiny, slightly viscid when moist, quickly drying becoming satiny, with a nonstriate and nonappendiculate margin. The flesh is white, about 3 - 5 mm thick over the stem, and relatively firm.
Gills are free at maturity, white to cream white, up to 6 mm broad, somewhat uneven on the edges, with a finely flocculent edge in young specimens. The short gills are subtruncate for the most part, some are sharply truncate.
The stem is 85 - 105 × 7 - 13 mm, cylindric, white, stuffed then hollow, smooth with fine scales, with a soft round bulb at the base. The ring is membranous, thin, skirt-like, persistent, with a few vague striations on the upper side. The volva is limbate, white, membranous, arising from the top of the bulb, lacking an internal limb, with the top of the limb 25 - 30 mm from the top of the bulb.
The odor is lacking at first then a little disagreeable. Amanita verna is deadly POISONOUS.
Spores from those specimens that become yellow in KOH solution measure (8.0-) 8.2 - 11.0 (-11.9) × (5.7-) 6.0 - 7.5 (-8.5) µm and are broadly ellipsoid to ellipsoid, infrequently elongate and amyloid, according to RET''s observations. Clamps are absent at the bases of basidia. Spores measured by Neville and Poumarat are as follows: (8-) 9 - 11.5 (-12) × (5.5-) 6 - 8.5 (-9.5) µm and are subglobose to broadly ellipsoid to ellipsoid, infrequently elongate and amyloid.
Amanita verna was originally described from France and occurs with a
wide variety of trees including oak (Quercus).
There is no type specimen for Amanita verna. Its lectotype
is an illustration provided by Bulliard with the original description of
the species. Given this fact, how could one create a case for
a species concept of A. verna?
Prior to research into chemical spot testing (which had considerable and unfortunate impact on
the species concept of A. verna), A verna could be understood as follows: It
was an entirely white, toxic species of Amanita similar in general habitat to A. phalloides, and
usually occurring in the spring. It differed from the also entirely white A. virosa because
the latter often had an irregularly shaped cap and a rather shaggy stem. Moreover, the range
of A. virosa, while overlapping with that of A. verna extended much farther to the
north (well into Scandinavia). When microscopy was included in descriptions, it was noted that
A. verna by the previous delineation bore ellipsoid rather than globose or subglobose
spores—a fact that further segregated A. verna from A. virosa.
In the early Twentieth Century, a report appeared on the yellow reaction of a macrochemical spot test on A. virosa with KOH and the fact that this reaction was lacking in A. phalloides var. alba (Bataille, 1926). When this report was included in a larger work, Bataille (1948) replaced "var. alba" with "var. verna," apparently considering the names synonymous. The revised text name consequently interpreted to state that A. verna had been tested with KOH and failed to produce a color reaction. This interpretation was an error as is documented by Neville and Poumarat (2004). It appears that Bataille never tested A. verna, and the belief that he did and got a negative result is based on a misinterpretation.
Due to the misinterpretation, which was widely reported and eventually accepted without question,
a new name was introduced for the taxon illustrated above: Amanita decipiens
(Trimbach) Andary & Bon. This taxon was said to differ from the "true"
A. verna solely in having a yellow response to spot testing with KOH.
We propose that readers consider the following statements in addition to the above
1. Romagnesi (1984) stated that in the environs of Paris he had never seen A. verna
that was not reactive to KOH. Romagnesi pointed out that Bulliard's familiarity with
A. verna was undoubtedly based on material from the vicinity of Paris.
2. During the years 1990 to 2001 in the départements of Gironde and Landes,
Francis Massart, his colleagues, and
his correspondents carried out a search for material otherwise assignable to the above
general concept of A. verna and not reacting to KOH. They found that all
collected specimens that appeared to be A. verna reacted positively (yellow-orange) when tested with KOH. Duplicates of a number of their collections were sent to RET and
are listed in the "material examined" data field of the technical tab on this taxon page.
3. It is reasonable to base the interpretation of A. verna on material found
in the area from which the taxon in question was originally reported.
Hence, there is no evidence to contradict that proposal that A. verna reacts positively to
KOH solution. On the other hand there is much evidence to suggest that it does.
While this proposal seems to us logical and simple, this is of course no proof of its certainty.
We expect molecular studies to produce information that is relevant to the question of whether
there are separable taxa within Amanita verna.
Amanita verna or something similar and not positively reacting to KOH is
known from North Africa. Spores from North African material measured by Zhu L. Yang
were (8.5-) 9.5 - 12 (-14.5) × (6.0-) 6.5 - 8.0 (-10.5) µm and are broadly ellipsoid to
ellipsoid, occasionally elongate. These are, on average, larger and very slightly
narrower (proportionately) than those RET measured from KOH-positive, French material.
[For more extensive synonymy, see Amanita Nomenclator (t.b.d.).]
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.
11.iii.1995 F. Massart 95001 (in herb. F. Massart; RET 280-3 and 291-2)
B. Wolfe et al., Pringle Lab., Harvard
Amanita verna var. decipiens—in herb. J. Trimbach.
Agaricus vernus—Bulliard. 1782. Herbier France: pl. 108.
Agaricus vernus—Neville and Poumarat. 2004. Fungi Europaei 9: 582.
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.
KOH or NaOH - positive (strong yellow or orangish
yellow) on cap and stipe.
H2SO4 - positive
(purple-magenta) on gills.
Massart 95001, Puddu s.n. [mushroomobserver
composite data from all material revised by RET & CRC: [60/3/2] (7.5-) 8.0 - 10.9 (-11.9) × (5.7-) 6.0 - 8.0 (-8.5) µm, (L = 8.8 - 9.8 µm; L’ = 9.2 µm; W = 6.7 - 7.2 µm; W’ = 7.0 μm; Q = (1.10-) 1.15 - 1.57 (-1.70); Q = 1.23 - 1.39; Q’ = 1.32), hyaline, colorless, smooth, thin-walled, amyloid, broadly ellipsoid to ellispoid, rarely elongate, adaxially flattened, sometimes expanded at one end; apiculus sublateral, subcylindric to truncate-conic, rather broad proporitionately; contents monoguttulate to granular; white in deposit.
From protolog of var. decipiens:
[43°49'52" N/ 07°19'43" E], s.d. J. Trimbach B136
(holotype, in herb. J. Trimbach).
REPUBLIC: SOUTH MORAVIAN
REGION—Ratiškovice [48°55'15" N/ 17°09'42" E],
25.vi.2006 Dr. J. Borovička 9 (PRM; RET
Château la Sauque [44°40'56" N/ 0°31'39" W],
17.v.1988 F. Massart 88012 (in herb. F. Massart;
RET 291-1); La Hume, 20.v.1991 F. Massart 91005 (in herb.
F. Massart; RET 280-1), 11.iii.1995 F.
Massart 95001 (in herb. F. Massart; RET 280-3,
also p.p. as 291-2); Lugos
[44°28'53" N/ 0°52'57" W], 25.iv.1999 Francis
Massart 99003 (in herb. F. Massart: RET 298-3);
Salles [44°33'08" N/ 0°52'12" W], 6.v.1990 Francis
Massart 9005 (in herb. F. Massart: RET 280-2);
Saucats [44°39'07" N/ 0°35'47" W],
v.1994 André Cazenave s.n.
[F. Massart 94001] (in herb. F. Massart:
RET 291-5); Le Verdon-sur-Mer [45°32'35" N/
01°03'49" W], 25.iii.2001 Francis Massart 01001 (in
herb. F. Massart: RET 343-4).
LANDES—Biscarosse [44°23'40" N/
01°10'03" W], 1.v.2000 J. A. Camy s.n. [Massart
2001] (in herb. Massart; RET 313-8 and
SARDINIA—Prov. Oristano -
Monte Arci [ca. 39.7930° N/ 8.76154° E], 25.v.2015
Davide Puddu s.n. [mushroomobserver #204946]
—R. E. Tulloss and C. Rodríguez Caycedo
Information to support the viewer in reading the content of "technical" tabs
can be found here.
(Bull.: Fr.) Lam.
"European Springtime Destroying Angel"
1. Amanita verna, southwestern France.
2. Amanita verna, showing reaction to KOH solution, southwestern France.
Francis Massart - (1-2) southwestern France. Image 2 illustrating reaction to KOH solution.
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.