Amanita pelioma is named for its strong tendency to bruise blue-green on the bulb and stipe base and, sometimes, on volval remnants in other areas of the fruiting body. Field identification in the U.S. is possible based solely on the staining character; however, a poorly understood amanita with a similar reaction occurs in Mexico.
The cap ranges from grayish olive to grayish olivaceous buff to pale buff to pale grayish buff to nearly white and is 40 - 90 mm wide.
The gills are usually not white and sometimes are distinctly the color of coffee with milk or colored similarly to the cap or (reportedly) sometimes have a lavender tint; they are free and moderately crowded. Short gills are attenuate.
The exannulate stipe is quite slender (90 - 150 × 6 - 12 mm).
The spores measure (8.8-) 9.8 - 13.6 (-15.0) × (5.5-) 6.0 - 9.1 (-10.1) µm and are ellipsoid to elongate (rarely broadly ellipsoid or cylindric) and amyloid. Clamps are absent from bases of basidia.
Amanita pelioma is often associated with oak and pine.
The species is moderately common in the southeastern U.S. and along the U.S. Gulf Coast.
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.
πελιομα (Grk.), "bruise"—because of the blue-green stains at the stipe base.
10.vi.2000 D. P. Lewis s.n. [Tulloss 6-10-00-H] (RET 312-4)
B. Wolfe et al., Pringle Lab., Harvard
Coker. 1917. J. Elisha Mitchell Scient. Soc. 33(1/2): pl. 1. [See comments on accompanying description by Bas (1969: 466).]
Tulloss. 2000a. Boll. Gruppo Micol. G. Bresadola 43(2): 14, fig. 3.
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 (Bas 1969) is based on original research by R. E. Tulloss.
from protolog: Basidiomes medium-sized, rather slender.
from protolog: ca. 50 - 90 mm wide, grayish olive to grayish olivaceous buff to pale brownish gray to "nearly white," broadly paraboloid to plano-convex, probably smooth and shiny when exposed; context not described; margin non-sulcate, appendiculate; universal veil concolorous, at first as complete covering, disappearing over disc, pulverulent-flocculose, sometimes form pulverulent warts over disc, rarely as blue-green squamules near margin.
RET: 47 - 66 mm wide, pale grayish buff, planoconvex, dry, dull; context off-white, 4.5 mm thick at stipe, thinning evenly for four-fifths of the radius, then a membrane to margin; margin nonstriate, appendiculate, decurved at first, becoming finely rimose in age; universal veil as floccose-pulverulent warts, pale gray, darker than pileus, detersile, unchanging when bruised.
from protolog: free, crowded to moderately crowded, pale grayish olivaceous to pale pale grayish buff to pale brownish gray, sometimes with slight lavender tint, probably rather narrow, with flocculose edge; lamellulae probably attenuate.
RET: free to very narrowly adnate, without decurrent line on stipe apex, subcrowded, pale brown in mass and in side-view, unchanging when cut or bruised, 5.5± mm broad, broadest near pileus margin, with edges eroded and minutely flocculent (10× lens); lamellulae attenuate.
from protolog: ca. 90 - 150 × 8 - 12 mm, grayish buff to pale grayish-olivaceous buff to very pale grayish, usually with pale to deep blue-green staining at top of bulb, subcylindric or narrowing upward; bulb clavate to fusiform (ca. 15 - 25 mm wide) or poorly defined, sometimes radicating; context not described; partial veil apical, thick but fragile, breaking on expansion, deciduous; universal veil as concolorous, irregularly detersile pulverulent covering, sometimes as inconspicuous pulverulent flocculose to (rarely) squamulose remains near top of bulb, with the latter sometimes staining blue-green as stipe.
RET: 147± × 6.5 - 10+ mm, pale grayish buff, staining blue to blue green over lower one-third, narrowing upward, flaring at apex, finely flocculent near apex, minutely longitudinally striate (lens), minutely fibrillose below; context pale buff, unchanging when cut or bruised, solid, with larva tunnels slightly browner than surrounding context; bulb narrow, radicating; partial veil deciduous; universal veil in scales somewhat reminiscent of those on A. onusta, concolorous with stipe, bruising as stipe.
from protolog: Odor like "chloride of lime" or "old ham." Taste not recorded.
Odor strong, stale, disagreeable. Taste not recorded.
Syringaldazine spot test for laccase - negative throught basidiome. L-tyrosine spot test for tyrosinase - lightly positive in lamellae and pileus context, strongly positive in stipe context at apex and in lower stipe. Paracresol spot test for tyrosinase - positive throughout basidiome with strongest reactions in stipe context at apex and in lower stipe. Test vouchers: ??.
from protolog: with "distinct" gelatinized layer developing over disc; filamentous hyphae 2 - 10 (-15) μm wide (in gelatinized layer 2 - 5 μm wide), interwoven to radial, ; vascular hyphae sometimes very conspicuous.
from protolog: On pileus: elements over disc with parallel anticlinal orientation, more disordered toward margin; filamentous hyphae scattered; inflated cells dominating, yellow to yellowish, subglobose to clavate, for the most part smaller than 55 &time; 50 μm, infrequently up to 80 &time; 50 μm, in chains. On stipe: similar to tissue on pileus, but with cells more intensely yellow.
from protolog: longitudinally acrophysalidic; vascular hyphae rather abundant.
lamella edge tissue
from protolog: inflated cells small, ellipsoid to clavate, usually smaller than 25 × 20 μm, probably in chains.
from protolog: [20/1/1] (9.0-) 10.0 - 12.5 × (6.0-) 6.5 - 8.0 μm, (Q = 1.45 - 1.85; Q = 1.65), pale dingy yellowish, thin-walled, amyloid, ellipsoid to elongate; apiculus not described; contents subgranular to amorphous; cream to pale gray to olive buff to grayish buff in deposit. [Note: Coker may have observed elements of material from the lamella edges in the spore print which might have changed the apparent color.].
composite of data from all material revised by RET & CRC: [165/7/5] (6.5-) 9.5 - 13.6 (-22.5) × (5.4-) 5.8 - 9.1 (-11.8) µm, (L = 10.5 - 12.3 µm; L’ = 11.4 µm; W = 6.0 - 8.1 µm; W’ = 7.1 µm; Q = (1.20-) 1.40 - 1.88 (-2.22); Q = 1.49 - 1.76; Q’ = 1.62), hyaline, colorless, smooth, thin-walled, amyloid, ellipsoid to elongate, infrequently broadly ellipsoid, often adaxially flattened, occasionally subreniform, occasionally swollen at one end; apiculus sublateral, cylindric; contents mono- to multiguttulate; ?? in deposit.
protolog: Solitary to subgregarious. Terrestrial in mixed woods, holotype on poor, dry soil.
Solitary to subgregarious. North Carolina: At 230 m elev. With Quercus in mixed (predominantly hardwood) forest. Virginia: in mixed woods incuding Quercus, Pinus strobus, Acer, and Liriodendron tulipifera.
NORTH CAROLINA—Orange Co. - Chapel Hill, 23.ix.1914 H. R. Totten 1253 (holotype, NCU). TENNESSEE—Knox Co. - Knoxville, 6.xi.1939 L. R. Hesler 12225 (paratype, TENN), 6.vii.1943 L. R. Hesler 15789 (paratype, TENN).
MISSISSIPPI—Unkn. Co. - unkn. loc., 16.vii.1987 T. J. Baroni s.n. [D. T. Jenkins 2791] (in herb. David T. Jenkins, Univ. Alabama, Birmingham).
NEW YORK—Orange Co. - ca. Cornwall, Black Rock Forest [41°24′29″ N/ 74°01′18″ W], 4.ix.1988 W. Bakaitis 88-10 (NY).
NORTH CAROLINA—Rowan Co. - Rockwell, Saleeby-Fisher YMCA [35.5737° N/ 80.4266° W, 230 m], 4.vi.2011 Matthew Sherman s.n. [mushroomobserver.org #68682] (RET 476-5).
TEXAS—Angelina Co. - 5 to 6 km N of Zavalla (sp?), Lewis Cemetery, 30.v.1982 D. P. Lewis 3062 (F n.v.; RET 012-6). ?? Co. - ??, N end of Turkey Creek Tr., 14.x.1979 D. P. Lewis 2057 (F n.v.; RET 012-7). ?? Co. - ??, Beech Crk. along Tr., 1.vii.1982 D. P. Lewis 3120 (F n.v.; RET 012-5). Hardin Co. - 16 km N of Silsbee, Big Thicket Nat. Preserve, Jack Gore Baygall Unit (NAMA 2000 foray 6), 10.vi.2000 "Dan" s.n. [Tulloss 6-10-00-E] (RET 312-5), D. P. Lewis s.n. [Tulloss 6-10-00-H] (RET 312-4). Unkn. Co. - unkn. loc., 26.x.1985 Texas Mycol. Soc. foray participant s.n. [Tulloss 10-26-85-C] (RET 132-6).
VIRGINIA—Franklin Co. - Ferrum, ca. Ferrum College, 4.viii.1982 O. K. Miller, Jr. & H. H. Miller 19940 (VPI 1587).
from protolog: "The type collection consists of only the young specimen depicted on the coloured plate publihed by Coker (1917: pl. 1); it is not accompanied by field-notes. The foregoing description of macroscopical characters is based on observations on the specimens of the collections cited, on the coloured plate of the type, and on the descriptive notes on collections 308, 314, 460, and 791 published by Coker (1917) under Amanita chlorinosma form A.
"The type specimen has abundant spores, but its tissues are difficult to study so that in the future, the microscopical characters must be carefully checked. Hesler 12225 and 15789 are both immature, although in the latter a few somewhat strangulated spores, measuring 12 - 14.5 × 6 - 8 μm could be found. In my experience, however, the first spores of a fruit-body are often somewhat aberrant in shape and/or size.
"Amanita pelioma represents the main part of what Coker called A. chlorinosma form A. At least one of the collections cited by Coker under this name and said to be intermediate between this form and typical A. chlorinosma, however, appeared to belong to...A. microlepis.
Characterized of A. pelioma are the greyish-olivaceous buff tinges of the complete fruit-body, gills included, the stronglypulverulent, concolorous volva consisting at least partly (at centre of cap) of erect, parallel rows of rather small inflated cells, the usually blue-green base of the stem, and the absence of clamps.
"It is the last mentioned character, together with the size of the spores (10 - 12.5 × 6.5 - 8 μm in A. pelioma against 8.5 - 10.5 × 5 - 6 μm in A. chlorinosma), and the somewhat different structure of the volva that make it impossible to consider A. pelioma a mere colour form of A. chlorinosma.
"Small pale forms of A. pelioma may be difficult to distinguish from A. cinereoconia, but that has white to pale cream gills and white, narrower spores (breadth 5 - 6.5 μm).
"Amanita longipes...resembles A. pelioma in many aspects. Among other things in common with A. pelioma the centre of the cap becomes denuded with age. But A. longipes is probably whitish and has slightly more slender, often somewhat strangulated spores. Moreover, in the remnants of the volva hyphae are rarer, which makes the microscopical structure of the volva of A. longipes more like that in A. chlorinosma."
Now that A. longipes has been validated and described based on a large number of collections (Tulloss and Jenkins 1985), we can say that the two species are very unlikely to be confused in the field. Amanita longipes is indeed nearly entirely pure white, lacks any sign whatsoever of blue-green staining, has whitish gills, etc. A comparison of the sporographs of A. pelioma and A. longipes is provided in the following figure:
A comparison of the sporographs of the present species and A. cinereoconia is provided in the following figure:
A. comparison of the sporographs of the present species and A. chlorinosma is provided int he following figure:
The reader may wish to compare the present species with Amanita sp-M34.
—R. E. Tulloss and C. Rodríguez Caycedo
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1. Amanita pelioma, Mississippi, U.S.A.
2. Amanita pelioma, Texas, U.S.A.
3. Amanita pelioma, possibly North Carolina, U.S.A.
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