PILEUS: 23 - 105 mm wide, black at first then dark brown (almost black) at center to 6E7 or paler toward margin, becoming shiny when dry, ovoid to hemispheric at first then obtusely convex expanding to plano-convex, becoming virgate in age; context white 4^± mm thick, unchanging when cut; margin not striate, nonappendiculate, incurved to decurved; universal veil absent or in detersile, appressed submembranous, fibrillose to cottony, gray to dark brownish gray patches with pallid undersides and margins or in detersile warts, dark brownish gray or (pinkish) gray with darker gray centers and with pallid margins, in all cases developing rusty or fulvous spots.

LAMELLAE: free to very narrowly adnate, close to crowded, white, becoming pale orangish cream or darker (5A3 to 5A5 or 7.5YR 7-8/6) when dry, 5^± mm broad, with margin minutely fimbriate (10× lens); lamellulae truncate.

STIPE: 40 - 100 × 10 - 30 mm, pallid with dense layer of longitudinally arranged gray fibrils, white when young, developing pinkish orange stains with age and near base with handling or as dark as 5C-D4 at maturity, subcylindrical to subventricose; bulb subradicating, splitting longitudinally at broadest point; context white; partial veil subapical to superior, membranous, pendant, flaring, persistent, white above, pale gray below, sometimes striate above; universal veil gray, forming two to three concentric rings (around top of bulb) of coarse floccose minutely verruculose pyramidal to subpyramidal warts with dark peaks, with patch of submembranous gray material (limbus internus?) found on lower stipe of one specimen.

PILEIPELLIS: 225 - 290 µm thick, some brown pigment dissolving in mount (wetted with ethanol, mounted in 2% KOH), extensively gelatinizing; filamentous, undifferentiated hyphae 1.8 - 6.0 µm wide, interwoven, branching, disordered on surface, below surface subradially arranged, many with dark brown intracellular pigment scattered throughout except for hyphae nearest surface and nearest transition to pileus context; vascular hyphae 1.0 - 6.0 µm wide. PILEUS CONTEXT: filamentous, undifferentiated hyphae 3.2 - 21.5 µm wide, branching, tangled, occasionally coiling, loosely interwoven in open lattice; acrophysalides clavate to elongate to ellipsoid, up to 138 × 80 µm, terminal or in chains (then not so fully inflated), with walls thin or very slightly thickened; vascular hyphae 5.8 - 12.0 µm wide, relatively common. LAMELLA TRAMA: bilateral; w_cs = 45 - 65 µm; central stratum including narrowly subfusiform intercalary cells; subhymenial base comprising divergent inflated cells singly or in short chains, diverging in smooth curve, often elongate and apparently all intercalary, mixed with smaller cells of other forms and filamentous, undifferentiated hyphae, with angle of divergence 45° - 60°; filamentous, undifferentiated hyphae 2.0 - 8.5 µm wide, branching; inflated cells ellipsoid to ovoid to elongate, up to 74 × 35 µm, thin-walled; vascular hyphae 1.5 - 4.5 µm wide. SUBHYMENIUM: w_st-near = 20 - 50 µm; w_st-far = 35 - 65 µm; cellular (pseudoparenchymatous), 5 - 7 cells deep; basidia arising from small ovoid to subglobose to clavate cells in branching chains or from short inflated or uninflated hyphal segments. BASIDIA: 37 - 55 × 9.0 - 12.2 µm, 4- or infrequently 2-sterigmate, thin-walled; clamps not observed. UNIVERSAL VEIL: On pileus: filamentous, undifferentiated hyphae 1.0 - 14.0 µm wide, branching, plentiful in upper surface of warts; inflated cells dominant throughout warts except at upper surface, gelatinizing at interface with pileipellis, hyaline or with pale grayish brown intracellular pigment, elongate-ventricose to ellipsoid to ovoid to subglobose, up to 56 × 47 µm, thin-walled, terminal, single or in short chains; refractive hyphae 2.2 - 12.0 µm wide, branching, locally plentiful (especially near upper surface). On stipe base: Very similar to that on pileus, but differing as follows: somewhat more gelatinized and with somewhat larger proportion of filamentous hyphae more commonly in fascicles; inflated cells somewhat larger, up to 73 × 53 µm; vascular hyphae 1.5^± µm wide, uncommon. STIPE CONTEXT: longitudinally acrophysalidic; filamentous, undifferentiated hyphae 1.8 - 11.5 µm wide, branching, plentiful, often in fascicles of those of smaller diameter; acrophysalides up to 271 × 125 µm, most narrower, with walls thin or very slightly thickened; vascular hyphae 1.5 - 6.5 µm wide, sometimes appearing intermixed in fascicles of filamentous, undifferentiated hyphae, occasionally forming fascicles nearly entirely of vascular elements. PARTIAL VEIL: almost entirely of interwoven branching filamentous, undifferentiated hyphae 2.5 - 9.5 µm wide, in large part subradially arranged, sometimes in fascicles; inflated cells scarce, terminal, clavate to broadly clavate, up to 59 × 37 µm; vascular hyphae 2.0 - 11.0 µm wide, locally plentiful in knots and tangles.

BASIDIOSPORES: [127/6/2] (7.5-) 8.8 - 11.2 (-12.5) × (5.5-) 6.5 - 8.2 (-9) µm, (L = 9.3 - 10.6 µm; L' = 10.1 µm; W = 6.9 - 7.5 µm; W' = 7.2 µm; Q = (1.11-) 1.28 - 1.60 (-1.74); Q = 1.35 - 1.47; Q' = 1.40), amyloid or slightly so, hyaline, colorless, with walls thin or sometimes thickened in apical region, smooth, subglobose to broadly ellipsoid to ellipsoid, occasionally elongate, adaxially flattened or slightly so; apiculus sublateral, cylindric, rather small; contents guttulate; color in deposit unknown.

Distribution and habitat: Gregarious to subgregarious, at up to 2700 m elev.  Under Q. humboldtii in loamy soil.

Material examined: COLOMBIA: DPTO. BOYACÁ-Mpio. San Miguel de Sema - rd. from Simijacta to San Miguel de Sema, 9.v.1987 R. E. Halling 5250 (COL, holotype; NY, isotype). DPTO. NARIÑO-Mpio. Pasto - vereda "La Josefina," km 17, rd. from Pasto to Chachagüí, 20.xi.1988 A. E. Franco-M. 164 (NY & PSO, paratypes).

DISCUSSION

Amanita picea is a medium-sized mushroom with a shiny black pileus and plentiful pyramidal to subpyramidal grayish warts in circles on the base of the stipe and, if not lost, irregularly dispersed or confluent as patches on the pileus.

In the field, this unique and easily recognizable entity looks like a black form of Amanita muscaria (L.:Fr.) Lamarck, but it can be separated easily from section Amanita by its amyloid spores.

Recent lists of Amanita species known from South America are available (e.g., Raithelhuber, 1986; Garrido & Bresinsky, 1985; Garrido, 1987). In these sources we find no taxon reported in Amanita section Validae (Fr.) Quél. with a spore length/breadth ratio similar to that computed for A. picea. The world literature contains descriptions of only four taxa in this section with similar spore size, although the values of Q determined for A. picea are very commonly found in species of section Validae. The four taxa with similar spores are macroscopically quite dissimilar from A. picea:

• Amanita bharatensis Sathe & David (Sathe et al., 1980) of southwestern India has a bright red pileus, white universal veil material, slightly larger spores and may belong in Amanita section Amanita; the protologue strongly suggests A. muscaria var. muscaria except for the report of faintly amyloid spores.
  
  
• Amanita flavorubens (Mont. & B.) Sacc. of eastern North America is yellowish with bright yellow universal veil material that is never left in subpyramidal warts. There are no rings of warts on the lower stipe and bulb, and flesh in the stipe base and bulb slowly stain wine-red.
  
  
• Amanita griselloides D. A. Reid (1980) of Australia has a silvery gray pileus and a complex universal veil; it may belong in section Lepidella.
  
  
• Amanita rubescens (Pers.:Fr.) Pers. of Europe has a pallid to brown pileus, lacks rings of warts on the lower stipe and bulb, and develops red-brown staining throughout the basidiocarp.

Garrido, N. and A. Bresinsky. 1985. Amanita merxmuelleri (Agaricales), eine neue Art aus Nothofagus-Wäldern Chiles. Bot. Jahrb. Syst. 107: 521-540.

Raithelhuber, J. 1986. Amanitaceae in Südamerika. Metrodiana 14: 3-21.

Reid, D. A. 1980. A monograph of the Australian species of Amanita Pers. ex Hook. (Fungi). Austral. J. Bot. Suppl. Ser. 8: 1-96.

Sathe, A. V., S. Deshpande, S. M. Kulkarni and J. Daniel. 1980. Agaricales (mushrooms) of southwest India. (Maharashtra Assoc. for the Cultivation of Science Research Institute, Pune). 114 pp.

Tulloss, R. E. 1991. Amanita morrisii -- history, taxonomy, and distribution. Mycotaxon 40: 281-286.

Tulloss, R. E., C. L. Ovrebo and R. E. Halling. 1992. Studies on Amanita (Amanitaceae) from Andean Colombia. Mem. New York. Bot. Gard. 66: 1-46.

Last changed 20 October 2009.
This page is maintained by R. E. Tulloss.
Copyright 2001, 2009 by Rodham E. Tulloss.