The following text is based on original research of R. E. Tulloss.
The dull .cap of A. praecox is 35 - 70 mm wide, yellowish with tints of orange and gray or pale tan with a slightly darker center or pale yellow overall or brownish yellow to brown in the center and cream to pale yellow near the margin, and unchanging when cut or bruised. The cap's shape is convex with a decurved margin at first, then planoconvex; it is subumbonate to umbonate, may become concave with age, is often tacky, and is viscid when wet. The cap's flesh is white or concolorous with the skin of the cap but paler, unchanging when cut or bruised, slightly pigmented under the cap's skin (especially with a brown tint in the center), and 2.5 - 3.5 mm thick over the stem. The cap's margin is striate (with striations occupying 20% to 25% of the cap's radius) and nonappendiculate. Volval remnants on the cap are absent or take the form of a cottony patch or patches; the remnants are submembranous and white to cream.
The gills of this species are free with a slight decurrent line on the upper stem or narrowly adnate with a decurrent tooth or line on the upper stem. The gills are close to subcrowded, white to cream in mass, ?? in side view, unchanging when cut or bruised, and 4 - 5 mm broad. The short gills are truncate to subtruncate to subattenuate, of diverse lengths, and unevenly distributed.
The stem is 58 - 135 × 5 - 16.5 mm, white to whitish to off-white to cream, becomes brown when handled, is cylindric or narrows upward, and flares at its top. There is minute pulverulence near the top of the stem (10× lens), below which, the stem is minutely fibrillose (10× lens). The bulb of the stem is starkly white, occasionally has white mycelial "threads" extending from its base, and measures 15 - 32 × 11 - 28 mm. The flesh of the stem is moist and pale yellow with cream streaking to sordid white to whitish to pale cream and hollow or partially stuffed with white cottony material. The stem's ring is evident only in young specimens; it has a thickened margin, is superior to median, white to whitish to cream, submembranous, and is easily lost. The volva takes the form of two concentric white ridges on top of the stem's bulb. The inner ridge (sometimes missing) representing the remains of the limbus internus (this material may also be left on the stem where it appears as sub-felted, white material). The outer ridge is sometimes a well-defined cottony white submembranous limb.
Odor and taste have not been recorded for this mushroom.
The spores measure (6.3-) 7.3 - 9.8 (-12.6) × (5.6-) 7.0 - 9.1 (-11.9) µm and are globose to subglobose to infrequently broadly ellipsoid (rarely ellipsoid) and inamyloid. Clamps are infrequent at, or absent from, bases of basidia.
Nearly always associated with Canadian Hemlock (Tsuga canadensis). One of the first amanitas to appear in northwestern New Jersey (hardwood-Canadian Hemlock forest) in June.—R. E. Tulloss
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The following material is based upon original research by R. E. Tulloss.
35 - 70 mm wide, slightly less orange and more gray than 4A3 or pale tan (4B4) with slightly darker disc or pale yellow throughout or disc brownish yellow to brown with margin cream to pale yellow, unchanging when cut or bruised, convex with decurved margin, then planoconvex, subumbonate to umbonate, becoming concave with age, tacky, viscid when wet, dull; context white or concolorous with pileipellis but paler, unchanging when cut or bruised, slightly colored under pileipellis especially with brown tint in disc, 2.5 - 3.5 mm thick at disc, thinning evenly to margin or for three quarters of radius and then membranous to margin; margin striate (0.2 - 0.25R), nonappendiculate; universal veil absent or as a cottony patch or patches, submembranous, white to cream.
free with slight decurrent line to narrowly adnate with decurrent tooth or line, close to subcrowded, white to cream in mass, ? in side view, unchanging when cut or bruised, 4 - 5 mm broad, with white edge finely fibriate (lens); lamellulae truncate to subtruncate to subattenuate, ?, of diverse lengths, unevenly distributed.
58 - 135 × 5 - 16.5 mm, white to whitish to off-white to cream, browning to the touch, cylindric to narrowing upward, flaring at apex, minute pulverulence near apex (lens), minutely fibrillose (lens) below, longitudinally striate; bulb starkly white, occasionally with white mycelial "threads" notable on base, 15 - 32 × 11 - 28 mm; context "moist pale yellow tone beneath cream streak[s]" to sordid white to whitish to pale cream, hollow, with hollow portion descending into the bulb on occasion, sometimes partially stuffed with white cottony material, with 2 - 3 mm wide central cylinder; partial veil evident only in young specimens, with thickened margin, superior to median, white to whitish to cream, submembranous, easily lost; universal veil as two concentric white ridges on top of bulb, twith inner ridge (sometimes missing) representing remains of limbus internus (sometimes left on stipe at or below midpoint as sub-felted, white material), with outer ridge sometimes well-defined cottony white submembranous limb up to 5 mm high often becomeing appressed to stipe base.
Spot test for laccase - negative throughout. Spot test for tyrosinase (L-tyrosine) - positive throughout, but somewhat pallid in lamellae. Spot test for tyrosinase (paracresol) - positive throughout in less than 3 min. Test vouchers: Tulloss 6-21-86-B and 6-20-87-A.
filamentous, undifferentiated hyphae interwoven, subradially arranged, gelatinizing, 2.1 - 4.9 µm wide, pigment restricted to hyphae that are not gelatinizing; vascular hyphae present, ?.
filamentous, undifferentiated hyphae 1.4 - 11.9 µm wide; acrophysalides globose to subpyriform (up to 50 × 40 µm) to ovoid (up to 79 × 35 µm) to clavate (up to 55 × 13.3 µm); vascular hyphae common, up to 14.7 µm wide; clamps ?.
bilateral, ? central stratum ?, angle of divergence ?; filamentous, undifferentiated hyphae 2.1 - 11.9 µm wide, branching; inflated cells elongate, up to 126 × 28 µm; vascular hyphae present, branching, ?.
On pileus: elements irregularly disposed; filamentous, undifferentiated hyphae moderately abundant, branching, 2.3 - 9.8 µm wide, occasionally constricted at septa, with walls thin or slightly thickened, sometimes in broad fascicles (?perhaps forming very thin surface layer); inflated cells abundant, with walls often 0.5 - 0.8 µm thick (often not apparent once gelatinization has begun), globose to subglobose to subpyriform to broadly ellipsoid to ellipsoid to ovate to broadly fusiform (up to 83 × 58 µm) or clavate to allantoid to bacilliform (up to 114 × 30 µm), terminal singly or in short chains; vascular hyphae not observed; clamps not observed. On stipe base: filamentous, undifferentiated hyphae branching, 1.4 - 9.1 µm wide, abundant, irregularly disposed; inflated cells terminal, singly or in short chains, subglobose to ovoid (up to 112 × 50 µm), bacilliform (up to 77 × 21 µm); vascular hyphae rare or absent.
tissues poorly rehydrating; filamentous, undifferentiated hyphae abundant, frequently branching, 3.5 - 8.4 µm wide; inflated cells in short terminal chains, broadly ellipsoid to ellipsoid to elongate to cylindric to bacilliform, up to 55 × 32 µm; vascular hyphae present, ?; clamps not observed.
[286/14/13] (6.3-) 7.3 - 9.8 (-12.6) × (5.6-) 7.0 - 9.1 (-11.9) µm, (L = (7.6-) 7.9 - 9.3 µm;
L’ = 8.6 µm; W = (7.1-) 7.3 - 8.4 µm; W’ = 7.9 µm; Q = 1.0 - 1.17 (-1.42); Q = 1.05 - 1.10 (-1.11);
Q’ = 1.08, thin-walled, smooth, hyaline, colorless, inamyloid, globose to subglobose to broadly ellipsoid, infrequently ellipsoid, occasionally adaxially flattened; occasionally flask-shaped; contents dominantly monoguttulate with or without additional small granules; apiculus sublateral, truncate conic, up to 1.0 µm wide at base; white in deposit.
Solitary to subgregarious. Mainland of North America: on hillsides under Tsuga canadensis with or without Pinus sp. On the Isl. of Newfoundland: Known only with ??. [Tsuga canadensis is enitrely absent on the island.]
CANADA: NEWFOUNDLAND & LABRADOR—Isl. of Newfoundland - GMNP, McKenzie’s Brk. [49.4333° N/ 57.8816° W, 27 m], 4.x.2003 Isabelle Schmelzer s.n. [Tulloss 10-4-03-B] (RET 371-6). QUÉBEC—Lajemmerais - Contrecoeur, 2.vii.1995 Yves Lamoureux 2785 (CMM; RET 521-3, nrITS seq'd.).
U.S.A.: CONNECTICUT—New Haven Co. - Cheshire Twp., Sleeping Giant St. Pk. [41°26'02" N/ 72°53'03" W, 179 m], 23.vii.1992 NEMF92 foray participant s.n. [Tulloss 7-23-92-C] (RET 066-3).
MAINE—Cumberland Co. - Cumberland Ctr., 3.vii.1984 S. S. Ristich s.n. [Tulloss 7-3-84-SSR] (RET 056-4), 7.x.1985 S. S. Ristich s.n. [Tulloss 10-7-85-SSR1] (RET 212-4). Penobscot Co. - Orono, Univ. Maine, 10.viii.1991 NEMF91 participant s.n. [Tulloss 8-10-91-F] (RET 029-2). Unkn. Co. - unkn. loc., 12.viii.1983 unkn. coll. 8-12-83-H (RET ??); NEMF83 walk C.R. #5, 13.viii.1983 Al Northrup s.n. [Tulloss 8-13-83-E] (RET 105-10).
MASSACHUSETTS—Middlesex Co. - ca. Sudbury, Hop Brook March Cons. Area, 14.viii.1993 participant NEMF93 s.n. [Tulloss 8-14-93-F] (RET 096-3). Worcester Co. - Westbrook, Westboro Metropolitan Distr. Comm. land, 14.viii.1993 participant NEMF93 s.n. [Tulloss 8-14-93-C] (RET 095-4).
NEW JERSEY—Sussex Co. (Long Isl.) - Stokes St. For., 25.vi.1983 Rhoda Roper s.n. [Tulloss 6-25-83-A] (RET 218-7).
NEW YORK—Dutchess Co. - ca. Poughkeepsie, 5.vi.1983 E. R. Yetter 6-5-83-A-YE1 (RET 219-6); Taconic Herford Multiple Use Area, Pond Gut Section [41°44'25" N/ 73°45'59" W, 171 m], 16.vi.2011 Wm. Bakaitis s.n. (RET 479-1), 19.vi.2011 Wm. Bakaitis s.n. (RET 479-6). Monroe Co. - Rochester, Durand Eastman Pk., 5 km E of Genessee R. & 0.8 km from Lk. Ontario, 7.vi.1992 Leo J. Tanghe s.n. [Tulloss 6-7-92-LJT1] (RET 061-2).
PENNSYLVANIA—Lawrence Co. - McConnells Mill, 10.vi.1985 E. Johnson 6-10-85-EJ1 (RET 082-2). Pike Co. - Lehman Twp., Egypt Mills [41°07'33" N/ 74°57'29" W, 130-195 m], 27.vi.1982 R. E. Tulloss, M. A. King & E. R. Yetter [Tulloss] 6-27-82-B (RET 340-6), 26.vi.1985 R. E. Tulloss 6-26-85-B, [-C??] (RET ??219-3); Dingman's Ferry, Pocono Environmental Education Ctr. [41°10'17" N/ 74°54'52" W, 235 m], 21.vi.1981 M. A. King & R. E. Tulloss 6-21-81-L (RET 168-8); Dingman's Ferry, Pocono Environmental Education Ctr., Indian Ladders Tr. [41°11'30" N/ 74°54'36" W, 216 m], 20.vi.1987 Ray Fatto s.n. [Tulloss 6-20-87-A] (RET 087-1).
TENNESSEE—Sevier Co. - ca. Gatlinburg, GSMNP, hemlock grove ca. park entrance [35°42'14" N/ 80°04'15" W, 410 m], ?? R. E. Tulloss ?? [FU-0131] (RET ??).
WEST VIRGINIA—Ritchie Co. - N. Bend St. Pk., 28.v.2002 Donna M. Mitchell DMWV02-121 (DEWV 2765).
One of the first amanitas to appear in late Spring or early Summer in eastern North America.
This species has also been called Amanita sp-32 on this site and in publications, correspondence, and keys of RET.
—R. E. Tulloss
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