Amanita roanokensis has
very narrow spores, which commonly may be more than 4 times as long as they are wide.
The cap is starkly white and 50 - 120 mm wide, convex to plano-convex, sometimes with a slight umbo, white, cream
in the center, probably subviscid, with a nonsulcate, appendiculate margin. The cap is scattered with rather
small to large, thin, flat, white, submembranous patches of volva.
The gills are white, adnate or adnexed, and moderately crowded to crowded to rather distant, narrow to
moderately broad, and white to pallid. The short gills are obliquely truncate to attenuate.
The usually exannulate stipe is 70 - 140 × 7 - 20 mm and, subcylindrical or attenuate upward, solid, white, and
(at first) flocculose; at the stipe base is a spindle-shaped, somewhat rooting bulb. A weak annulus
may be noticed in young fruiting bodies. There is a distinct limbate volva at the top of the stipe's basal
bulb, but this may be hard to see when it collapses on the stipe.
The spores measure (12.0-) 12.8 - 17.1 (-19.5) × 3.6 - 4.9 (-5.0) µm and are
amyloid and cylindrical to bacilliform. Clamps are not found at bases of basidia.
Amanita roanokensis has an odor that is pleasant or "like cooking meat" at first, but later it is described as "like carrion" or "old bones."
This species is often associated with oak and pine.
It is moderately common in the southern part of the sandy Atlantic coastal plain of the 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.
Bas (1969): [50/3/3] (11.5-) 12.5 - 15.0 × 3.5 - 5.0 μm, (Q = 2.70 - 3.90; Q = 3.20 - 3.40), yellowish, thin-walled, amyloid, cylindric to bacilliform, "sometimes slightly bent at base or slightly constricted in middle," apiculus not described; contents refractive, granular; color in deposit not recorded. "[S]ome (about 1% in types of A. roanokensis and A. watsoniana, about 50% in Murrill F 10375) with amyloid, granular warts, especially on apical half" (Bas 1969: figs. 366, 368).
from type study of Amanita watsoniana by Jenkins (1979): [-/-/1] 11.3 - 14.1 (-15.6) × 3.9 - 4.7 μm, (Q = 2.90 - 4.00; Q' = 3.38),
hyaline, thin-walled, amyloid, cylindric to bacilliform, often adaxially flattened; apiculus sublateral, very short, truncate; contents guttulate;
color in deposit not recorded.
composite of data from all material revised by RET: [40/2/2] (12.0-) 12.8 - 17.1 (-19.5) × 3.6 - 4.9 (-5.0) μm, (L = 14.4 - 14.7 μm; L' = 14.6 μm; W = 4.1 - 4.4 μm; W' = 4.2 μm; Q = (2.62-) 2.73 - 4.08 (-4.67); Q = 3.32 - 3.70; Q' = 3.51), hyaline, colorless, smooth, thin-walled, amyloid, cylindric to bacilliform, occasionally subsigmoid or subsinuate; apiculus sublateral, proportionately small; contents ??; ?? in deposit.
Solitary. Florida: On humus. South Carolina: In flood plain in mixed forest containing Pinus and Quercus.
Bas (1969): U.S.A.:
FLORIDA—Alachua Co. - Gainesville, 1.vii.1942 W. A. Murrill F 10357 (FLAS). Columbia Co. - Camp O'Leno, 19.x.1941 W. A. Murrill F21875 (holotype of Venenarius watsonianus, FLAS).
NORTH CAROLINA—Dare Co. - Roanoke Isl., ca. Fort Raleigh, 17.ix.1927 W. C. Coker & Braxton 8255 (holotype of A. roanokensis, NCU).
from type study of Amanita watsoniana by Jenkins (1979):
U.S.A.: FLORIDA— Columbia Co. - Camp O'leno, 19.x.1941 W. A. Murrill F 21875 (holotype, FLAS).
FLORIDA—Brevard Co. - Melbourne, 10.xi.1984 Aaron Norarevian & E. R. Yetter 4 [Tulloss 11-10-84-#4] (RET 233-6). Duval Co. - Jacksonville, 9.xi.1984 A. Norarevian & E. R. Yetter 8 [Tulloss 11-9-84-#8] (RET 234-5). Seminole Co. - Altamonte Springs, 22.vii.1958 Paul O. Schallert 7-428 (K).
NORTH CAROLINA—Dare Co. - Hatteras Isl., N of Frisco, 16.vii.1981 R. E. Tulloss 7-16-81-C (RET 169-9), -D (RET 170-3), 17.vii.1981 D. C. & R. E. Tulloss 7-17-81-B (RET 169-8), -C (RET 170-6), -D (RET 169-6), -E (RET 170-2), -F (RET 170-4), -H (RET 169-7), -I (RET 170-5).
SOUTH CAROLINA—Greeneville Co. - Greer, ca. border with Spartanburg Co. [34°43'30.44" N/ 82°21'32.13" W], 14.vii.2000 M. A. & R. E. Tulloss 7-14-00-A (RET 313-7).
TEXAS—Hardin Co. - 6.5 km W of Silsbee, Roy Larson Sandlyand Sanctuary, 10.vi.2000 D. Pruden s.n. [Tulloss 6-10-00-J] (RET 312-3).
—R. E. Tulloss
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