Amanita xanthomitra

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name	Amanita xanthomitra
name status	nomen provisorum
author	Tulloss
english name	"Yellow Headband Ringless Amanita"
images	1. Amanita xanthomitra, Shark R. Co. Pk., Monmouth Co., New Jersey, U.S.A. 2. Amanita xanthomitra, Shark R. Co. Pk., Monmouth Co., New Jersey, U.S.A. 3. Amanita xanthomitra, Shark R. Co. Pk., Monmouth Co., New Jersey, U.S.A. 4. Amanita xanthomitra, Shark R. Co. Pk., Monmouth Co., New Jersey, U.S.A.
intro	The following based on original research of RET.
cap	The cap is 32-80 mm wide and has a deep olive center transitioning to yellowish olive and then white at the edge. The cap is bell-shaped to convex and remains unchanged when bruised or cut. The flesh of the cap is white to pale gray. The volval remnants are crumb-like warts which separate easily from the cap and are white at first then become pale gray to black at their highest points.
gills	The pale off-white gills are narrowly attached and close together. The plentiful short gills are squarely cut off, of diverse lengths, and are unevenly distributed.
stem	The mostly hollow stem is 84 - 135 × 5.5 - 12 mm and is white to pale cream with a yellowish tinge, becoming grayish at maturity or with handling. The stem is sometimes decorated with pale gray to brown fibrils in a chevron pattern. The stem narrows upward and flares at the top. The stem’s flesh is white and remains unchanged when cut or bruised. The volva barely covers the stem’s base and is whitish to pale cream. Volval remnants may be present as fragile cracking patches that are gray to dark gray and easily flake off.
odor/taste	Amanita xanthomitra is odorless. Its taste has not been recorded.
spores	The spores measure (7.7-) 8.4 - 12.6 (-13.6) × (7.3-) 8.0 - 12.2 (-13.3) µm and are inamyloid, globose to subglobose. Clamps are probably lacking at bases of basidia.
discussion	This species was originally found in the New Jersey Pine Barrens associated with oak and pitch pine. A specimen was also described from Pennsylvania in the loam of a mixed forest containing oak, eastern hemlock, and pine. There is photographic evidence that the species occurs as far north as Quebec. It may be found singly or growing in a small group.—R. E. Tulloss and N. Goldman
brief editors	RET

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.

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accession	locus	voucher	source

intro

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, with young specimens having a deep olive disc which transitions to yellowish olive then yellow and finally white at the margin, occasionally with 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, dull, 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 - 0.45R), nonappendiculate, sometimes developing fine dark radial lines on outer parts of ridges between striations; universal veil as crumb-like warts, white at first, soon becoming 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, 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 as appressed wavy line or lines (12 - 20 mm up from base of stipe), often with thin appressed cup whitish to pale cream, barely covering stipe base, 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.

basidiospores

send to graphing tool

[80/4/2] (7.7-) 8.4 - 12.6 (-13.6) × (7.3-) 8.0 - 12.2 (-13.3) µm, (L = 9.5 - 11.0 µm; L’ = 10.0 µm; W = 9.1 - 10.6 µm; W’ = 9.5 µm; Q = 1.0 - 1.09 (-1.19); Q = 1.03 - 1.06; Q’ = 1.04), hyaline, colorless, smooth, thin-walled, inamyloid, globose to subglobose, adaxially flattened, occasionally with some "giant" spores; contents mono- to multiguttulate to granular; apiculus sublateral, cylindric; 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.: MASSACHUSETTS—Middlesex Co. - ca. Sudbury, Hop Brook Marsh Cons. Area, 14.viii.1993 Jean Deprés s.n. [Tulloss 8-14-93-A] (NY; RET ??), R. Buttignol s.n. [Tulloss 8-14-93-B] (RET 094-10). NEW JERSEY—Burlington Co. - Audubon Rancocas Nature Ctr., 28.viii.2009 Rena Wertzer s.n. [Tulloss 8-28-09-B] (RET 437-2). Mercer Co. - Hopewell Twp., Stony Brook-Millstone Watershed Res., 18.ix.1994 R. E. Tulloss 9-18-94-A (RET 130-3). 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). PENNSYLVANIA—Clarion Co. - Clarion, St. Game Lands 63, Roberts Hill Rd. [41.1421° N/ 79.2830° W, 419 m], 6.viii.2011 Angie Miller s.n. [Tulloss 8-6-11-B, NAMA 2011-245] (F; RET 478-7). 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).

discussion

The following illustration provides a sporograph comparison between the present species and both A. borealisorora and A. sinicoflava:

This taxon was previously called Amanita sp. 46 in Tulloss' keys,, checklists, and correspondence.

citations

—R. E. Tulloss and C. Rodríguez Caycedo

editors

RET

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Spore Measurements by Collection