The following information is derived from the original description of A. demissa.
The cap of A. demissa is 15 - 35 mm wide, campanulate to plano-convex, becoming plane at last, sometimes slightly umbonate, sometimes slightly depressed at the center, grayish umber or umber-gray, paler toward margin, slightly viscid, with a 1/3 striate from margin toward the center. The flesh is thick over the center, soft, and white. The cap is sprinkled with minute, soft, scurfy, fuliginous, easily separable particles that form conical warts in the center.
The gills are free, not crowded, thin, and white.
The stem is 25 - 50 × 2 - 3 mm, brittle, attenuate, and hollow. Volval remnants are present at the base of the stem in concentric rings.
The odor of this mushroom is said to be slight and indistinct. The taste was not reported.
According to the original description, spores from dried material measure 6.4 - 8.5 (-10.1) × 4.7 - 6.4 µm (from fresh material, 7 - 9.5 × 5 - 6.5 µm) and are broadly ellipsoid to ellipsoid (occasionally, subglobose). Clamps were not observed at the bases of basidia.
This species was described from Singapore.—R. E. Tulloss
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The following material is derived entirely from the protolog of the present taxon.
from protolog: 15 - 35 mm wide, grayish umber to umber-gray, paler toward margin, becoming pale brownish gray or gray over disc and whitish at margin, campanulate to plano-convex, becoming plane at last, sometimes slightly umbonate, sometimes slightly depressed in center, presumably slightly viscid; context soft, white, 1.5 - 2.5 mm thick above stipe, very thin above lamellae; margin striate (0.3 - 0.35R); universal veil as sprinkling of minute, soft, scurfy, fuliginous, easily separable warts, 0.3 × 0.5 - 1 mm and as conical warts over disc.
from protolog: free, not crowded, white, thin, 1.5 - 3 mm broad, 34 - 43 primaries; lamellulae attenuate, 1 - 3 between each otherwise adjacent pair of lamellae.
from protolog: 25 - 50 × 2 - 3 mm (width measured at apex), pale grayish white with white apex or wholly pallid whitish, slightly fibrillose, narrowing upward; bulb 3 - 6 mm wide;, context hollow (cavity not drawn in all figures), brittle; partial veil narrow, pendent, median or submedian, "not spreading," white, with fuliginous scurfy particles on edge; universal veil as 1 - 3 faint uneven raised circles of fine grayish pruina on upper half of bulb (per figure).
from protolog: Odor slight and indistinct. Taste not recorded.
from protolog: comprising two layers; suprapellis as thin gelatinous matrix; subpellis somewhat thicker ungelatinized; filamentous hyphae brown, 1.5 - 3 µm wide (very distant and irregularly disposed) in suprapellis, up to 8 µm wide (crowded, slightly interwoven, radially organized) in subpellis. [Note: A suprapellis with colored hyphae rather sparsely populating a gelatinous matrix is known from several taxa in other sections of Amanita; e.g., A. flammeola, A. dunicola, and A. sampajensis in sect. Vaginatae come to mind.nbsp; This makes me wonder whether such colored hyphae in the suprapellis might be unusually colored vascular hyphae (which often may pass undamaged through a fully gelatinized suprapellis) or hyphae of an invading hyphomycete, in one or more of these cases.—ed.]
from protolog: "impossible to analyze in dried material."
from protolog: "impossible to analyze in dried material."
from protolog: 28 - 40 × 90 - 10.5 µm, dominantly 4-, rarely 3- or 2-sterigmate, with sterigmata 3 µm long; clamps not observed.
from protolog: On pileus: filamentous hyphae 2.5 - 6 µm wide, rather scarce; inflated cells dominating, 15 - 55 (- 80) µm wide, thin-walled, smooth, ca. globose to subglobose, with pale fuliginous contents, terminal mostly in long anticlinal chains or (sometimes) singly. On stipe base: filamentous hyphae plentiful, interwoven; inflated cells globoose to subglobose, brown.
from protolog: longitudinally acrophysalidic; acrophysalides cylindric to cigar-shaped, up to 420 × 45 µm, sometimes subtended by one similar cell or short chain of similar cells.
lamella edge tissue
from protolog: inflated cells 16 - 40 µm wide, scattered along gill-edge.
from protolog: "Terrestrial in forest; occurring every rainy season (March-April, Aug.-Sept.); developing quickly; nearly always solitary and scarce."
from protolog: SINGAPORE: Bukit Timah, 21.viii.1939 E. J. H. Corner s.n. (holotype, L), 3.ix.1940 E. J. H. Corner s.n. (paratype, L, watercolor only), xii.1940 E. J. H. Corner s.n. (paratype, L, watercolor only); Botanic Gardens, 18.viii.1940 (paratype, L, watercolor only).
from protolog: "Amanita demissa seems to possess all the characters of a small species of section Amanita, viz. a hollow stipe, a striate margin of the pileus and a narrow non-striate annulus. However, the spores are amyloid and therefore the species has to be placed in section Validae where it does not find close allies."
The present species was also recorded (but not collected) by Corner from "Mandai Rd. forest," Singapore.
Beeli described a central African specimen with dark pigmentation, a distinctly striate pileus margin, and amyloid spores—A. fuliginosa. A comparison of that species and the present one may be of interest.
—R. E. Tulloss
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Corner & Bas
1. Amanita demissa, Singapore.
2. Amanita demissa, Singapore.
3. Amanita demissa, Singapore.
Prof. E. J. H. Corner - (1-3) Singapore, illustration from original description (Corner & Bas, 1962)
reproduced by courtesy of Persoonia, Leiden, the Netherlands.
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