Name: Marasmius amazonicus
Citation: Hedwigia 43: 183 (1904)
Marasmius amazonicus Hennings, Hedwigia 43: 183. 1904.
TYPE. Lost (see below).
Pileus deep purple to deep lilac violet, the disc blackish purple (eg 56-J/L- 5 M&P) near center with numerous orange brown (“talavera”), near margin pale buffy orange (“capucin buff”) or every where buff dots which are oval to round and 2-4mm in diameter, glabrous, deeply sulcate almost to the disc, campanulate-convex to convex applanate, with umbilicate disc, 42-72 mm broad. Lamellae white or buff-cream, broad (6-16 mm broad), ventricose, intermixed with 0-1 lamellulae, not intervenose, with entire, not discolorous edge, free to removed from the apex of the stipe and then leaving uncovered a white, sulcate disc around the extreme apex of the stipe, distant (19-22 lamellae). Stipe deep chestnut to black, paler brown at apex when young, slightly longitudinally striate when dried, otherwise smooth, glabrous, shining, hollow, equal or
gradually and very slightly tapering upwards, terete and sometimes somewhat compressed, sometimes arising from a small socle which is covered by the basal mycelium, 80-145 X 2.5-3.5mm; basal mycelium tomentose, “cocoa” color. Context thin, white, toughish, inodorous.
Spores 12-21 X 3.5-4.8µ, oblong to fusoid, in profile often somewhat curved, attenuate towards the base, hyaline, thin-walled, smooth, inamyloid. Hymenium: basidia hyaline, 4-spored (?); cystidia none; cheilocystidia like epicuticular elements, but all hyaline. Hyphae hyaline, distinctly pseudoamyloid. Cortical layers: epicutis of pileus consisting of broom cells which are hymeniformly arranged; these hyaline to subhyaline seen individually (NH40H) but in thicker layer deep porphyry brown, individual setulae mostly hyaline or subhyaline but here and there some purple black setulae present, total measurements 15-18 X 9-10µ, main body often indistinct and reduced, setulae spinulose and subacute, tapering from a 2-2.7µ broad base, 5-9µ long, entirely inamyloid.
On trunks and on very rotten wood among leaf mold,in small groups,not cespitose. MATERIAL STUDIED. BOLIVIA. Beni: Vaca Diez, Guayaramerin, 8 Mar
B 1706 (LIL); 14 Mar 1956, B 1946 (LIL).
The species was originally described from Jurua miry, Amazonas, Brazil, collected by Ule. The type was conserved in Berlin where it was destroyed during the last war. The description however, leaves not the slightest doubt as to the identity of the material. This is the most spectacular species of South America as far as external appearance is concerned. A similar or analogous species from Cameroon, M. superbus Henn., differs in umbonate pileus with rugolose-venose and not dotted surface and, according to Hennings, collariate lamellae, and broader stipe. It belongs in section Globulares
ILLUSTRATION. Singer (1965), p1 14, fig 72.
source: Singer, Rolf. Flora Neotropica 17 – MARASMIEAE. New York: NYBG, 1976. Print.
Created: 2014-01-31 21:58:58 CST (-0500) by Parker V
Last modified: 2014-02-15 17:16:35 CST (-0500) by Danny Newman (myxomop)
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