| name |
Amanita xanthomitra |
| author |
Tulloss nom. prov. |
| name status |
nomen provisorum |
| english name |
"Yellow Headband Ringless Amanita" |
| etymology |
ξανθοσ, "yellow" (Grk.) + μιτρα, "head band" (Grk.); hence "[bearing a] yellow head band"—because of the yellow zone that is a striking character of young specimens |
| GenBank nos. |
Due to delays in data processing at GenBank, some accession numbers may lead to unreleased (pending) pages.
These pages will eventually be made live, so try again later.
|
| intro |
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 is based on molecular work by Dr.
L. V. Kudzma and other original research by R. E. Tulloss. |
| pileus |
32 - 80 mm wide, more yellow than 5D5 or more olive than 5C5 and 10YR 6/4 or browner than 2.5YR 6/4 or more saturated than 2.5YR 7/4, often darkest over disc, with young specimens having a deep olive disc which transitions to yellowish olive then yellow and finally white at the margin, occasionally with white or very pale margin persisting at maturity, sometimes with thin dark line developing along margin, campanulate at first, unchanging when bruised or cut, becoming convex to planoconvex and somewhat depressed, sometimes finally concave, dull, fiscid at first then faintly tacky to somewhat waxy; context white with pale sordid tint at times, faintly to intensely concolorous with pileipellis for 1± mm below same, unchanging when cut or bruised, 2 - 4.5 mm thick at stipe, thinning evenly for one half to three-quarters of radius, then membranous to margin; margin striate (0.3 - 0.5R), nonappendiculate, sometimes developing fine dark radial lines on outer parts of ridges between striations; universal veil as crumb-like or pyramidal warts (in latter form often plentiful and then densely concentrated over disc) or as confluent patches of varying sizes, white at first, soon becoming pale brownish to pale gray then gray and eventually black (at least on highest points), finely verruculose, detersile. |
| lamellae |
narrowly adnate without decurrent line on stipe apex or with a tiny decurrent tooth (lens), close, off-white to very pale cream in mass, white to very pale off-white to barely creamy white to slightly watersoaked white in side view, unchanging when cut or bruised, 3 - 8.5 mm broad, at first with white minutely flocculose edge, occasionally anastomosing; lamellulae truncate to subtruncate, unevenly distributed (in some material absent between all lamellae for ca. 20% or more of cap circumference), of diverse lengths, plentiful. |
| stipe |
84 - 135 × 5.5 - 12 mm, white to pale cream with yellowish ting, becoming grayish at maturity or handling in some specimens, rather strongly fibrillose in chevron-like pattern, with fibrils white at first, becoming pale grayish to dark gray to gray brown to black at maturity or with handling, narrowing upward, flaring slightly at apex; context white, unchanging when cut or bruised, concolorous in larva tunnels, hollow with some cottony white fibrils, with central cylinder 3 - 7 mm wide; exannulate; universal veil often as thin appressed cup whitish to pale cream barely covering stipe base, additionally (remains of limbus internus) as appressed wavy line or lines (12 - 20 mm up from base of stipe) pallid to pale brownish at first becoming black with age (persistent in exsiccata in this form) and having subtriangular cross-section, additionally sometimes a few small scattered cracking detersile patches (sometimes confluent), very fragile (submembranous, friable), pallid at first, becoming dark gray to black. |
| odor/taste |
Odorless. Taste not recorded. |
macrochemical
tests |
Syringaldazine, spot test for laccase - negative throughout. Paracresol, spot test for tyrosinase - rapidly positive throughout basidiome except negative in base of stipe. Test voucher: Tulloss 8-9-87-A. |
| basidia |
??, 4-sterigmate, ??. |
| partial veil |
absent. |
| lamella edge tissue |
sterile. |
| basidiospores |
[140/7/4] (7.7-) 8.7 - 11.9 (-13.6) × (7.3-) 8.4 -
11.5 (-13.3) µm, (L = 9.5 - 11.0 µm;
L’ = 10.1 µm; W = 9.1 - 10.6 µm;
W’ = 9.6 µm; Q = 1.0 - 1.09 (-1.19);
Q = 1.03 - 1.08; Q’ = 1.05), hyaline,
colorless, smooth, thin-walled, inamyloid, globose to
subglobose, infrequently broadly ellipsoid, at least
somewhat (and often distinctly) adaxially flattened,
occasionally with some "giant" spores present;
contents mono- to multiguttulate (with or
without additional small granules) to granular;
apiculus sublateral, cylindric, often
prominent; white in deposit. |
| ecology |
Solitary to subgregarious. New Jersey: In sand of oak-pine (Quercus-Pinus rigida) barrens. Pennsylvania: At ca. 420 m elev. In loam of mixed forest with Quercus, Tsuga canadensis, Pinus, etc. |
| material examined |
U.S.A.:
CONNECTICUT—New London County -
Griswold, Hopeville Lake St. Pk. [41.608° N/
71.9232° W, 67 m], 31.vii.2015 Judith E. s.n.
[Tulloss 7-31-15-H] (RET 704-5, nrITS & nrLSU
seq'd.).
FLORIDA—Hendry Co. - Okaloacoochee
Slough St. For. [26.56625° N/ 81.31205° W, 9 m],
20.ix.2014 Ben Dion s.n. [mushroomobserver #179787]
(RET 652-7, nrITS & nrLSU seq'd.).
MAINE—Sagadahoc
Co. - Georgetown, Reid St. Pk., 8.viii.2014
Elaine Quaroni s.n. [Tulloss 8-8-14-L]
(RET 626-5, nrITS seq'd.).
York Co. - unkn. loc.,
28.vii.2014 Herber Baker s.n. [mushroomobserver #171750]
(RET 645-4, nrITS & nrLSU seq'd.), [mushroomobserver #171596]
(RET 645-9, nrITS
seq'd.).
MASSACHUSETTS—Dukes Co. - Martha's
Vineyard, Beetlebung’s Corner [41.3428° N/
70.7442° W, 25 m], 14.viii.2014
William McAdoo s.n. (RET 657-9,
nrITS-LSU seq'd.).
Middlesex Co. - ca.
Sudbury, Hop Brook Marsh Cons. Area, 14.viii.1993
Jean Deprés s.n. [Tulloss 8-14-93-A]
(NY; RET 095-1, nrITS seq'd.), R. Buttignol s.n.
[Tulloss 8-14-93-B] (RET 094-10,
nrITS seq'd.).
MICHIGAN—MaComb Co. - Shelby
Twp., Stony Creek Metropark [42.7298° N/ 83.0592°
W, 253 m], 24.viii.2018 Huafang Su s.n.
[mushroomobserver
#329539]
(RET 845-4, nrITS & nrLSU seq'd.).
NEW JERSEY—Burlington Co. - Audubon
Rancocas Nature Ctr., 28.viii.2009 Rena
Wertzer s.n. [Tulloss 8-28-09-B] (RET 437-2,
nrITS seq'd.). Mercer
Co. - Hopewell Twp., Bell Laboratories (Lucent)
[40°21’39” N/ 74°43’29” W], 18.vii.1984 R. E.
Tulloss 7-18-84-D (RET 242-2); Hopewell Twp.,
Stony Brook-Millstone Watershed Res., 18.ix.1994
R. E. Tulloss 9-18-94-A (RET 130-3, nrLSU seq'd.).
Monmouth Co. - Shark River Co. Pk.
[40°12’18” N/ 74°05’44” W, 16 m], 9.viii.1987 Ed
Van Schoick s.n. [ Tulloss 8-9-87-A] (RET 180-7),
5.viii.2009 R. E. Tulloss & F. Wartchow
[Tulloss] 8-5-09-A (RET 436-1, nrITS seq'd.).
NEW YORK—Dutchess Co. - Clinton Corners,
Walnut Lane, Boyer Farm, 12.ix.1990 William
Bakaitis 90-189 (RET 011-3, nrITS seq'd.).
NORTH CAROLINA—Haywood Co. - GSMNP,
Cataloochee sector, vii.2008 Debbie Viess s.n.
(RET 445-9, nrITS & nrLSU seq'd.).
PENNSYLVANIA—Lackawana Co. - prop. at SE end of Thornhurst Rd. [41.1785° N/
75.5806 W, 472 m], 19.vii.2015 David Wasilewski s.n.
[mushroomobserver
#210820]
(RET 706-4, nrITS seq'd.). Unkn. Co. -
Caledonia St. Pk., ca. border of Franklin &
Adams Cos., 12.viii.2005 L. H. P. Yarroll s.n.
[Tulloss 8-12-05-C] (RET 386-4, nrITS seq'd.).
VIRGINIA—Hanover Co. - unkn. loc., 11.vii.2021
Penny Firth s.n. [mushroomobserver
#464407]. |
| discussion |
The following illustration provides a sporograph
comparison between the present species and both
A. rhacopus and A.
sinicoflava:
The presence of "giant spores" in one of the three
specimens of RET 280-7 will continue to distort the
sporograph of this species until several more
collections are made that do not add to the number
of "giant spores" in the spore sample for A.
xanthomitra. We estimate that the 95th
percentile of spore length will stabilize ca. 11.0
μm.
This taxon was previously called Amanita sp.
42 in Tulloss' keys, checklists, and correspondence
and was previously designated A. sp-N59 on
this site.
[Note: (June 12, 2014) This concept (based on
cited collections) is a mix of two or more taxa
according to sequencing of the nrITS gene.
The segregation of the taxa is in progress.—RET] |
| citations |
—R. E. Tulloss and C. Rodríguez Caycedo |
| editors |
RET |
|
Spore data sets and their composite