Search on : Taxa descriptions

 


 
 Add this item to the list  Pleurotus hyacinthus sp. nov. Figure 34
   
Description type:Original description 
Description:Pleurotus hyacinthus sp. nov. Figure 34
Borneo. Typus: RSNB 5750 in Herb. Corner.
Caespitose, wholly pale lilac pink, fading pale fawn vinaceous; mycelial fibrils pale lilaceous. Pileus 2-8 cm wide, often excentric but not lateral, convex to umbilicate, then piano-infundibuliform and pervious to the base of the stem, smooth, substriate;, margin incurved. Stem 2-7 cm x 3-9 mm, 2-3 mm at the base, often strongly attenuate downwards, smooth, hollow. Gills deeply decurrent, crowded, thin, narrow, 36-44 primaries 1.5-2.5 mm wide, 5-6(-7) ranks, edge entire. Flesh thin, brittle, becoming rather soft, hygrophanous, tougher in the stem. Smell none or slightly soapy-fragrant.
On dead wood at the base of a dead standing trunk, or on the ground, in the forest. Bomeo, mt. Kinabalu.
Spores 5-6.5 x 3-4 µm, white (? pinkish), smooth, ellipsoid, inamyloid. Basidia 20-25 x 6-7 µm; sterigmata 4, 4-5 µm long; no acerose basidioles; subhymenium narrow, with 2-3 µm interwoven hyphae. Cheilocystidia as small sterile basidia, often subventricose and with a short process, as a narrow sterile edge to the gill, but collapsing. Pleurocystidia none.
Hyphae monomitic, clamped, inflated, often constricted at the septa, the cells 25-250 x 3-40 µm, often irregularly swollen, longitudinal, becoming slightly thick-walled in the stem, mostly up to 25 µm wide in the pileus, somewhat narrower and descending in the gills; oleiferous hyphae 2-4 µm wide, sparse.
Surface of the pileus inoderm with a few shortly divergent hyphal ends or processes, without a conspicuous layer of narrow hyphae at the Surface. Surface of stem similar but with some narrow superficial hyphae.
Collections: RSNB 1904, Kinabalu, Bembangan R., 1800 m alt, 20 Aug. 1961, on the ground; RSNB 5750, Kinabalu, Mesilau 1600 m alt. 12 March 1964.
This fungus suggests, at first, a large and well-developed state of Trogia infundibuliformis but the structure is that of Pleurotus. The rather brittle pileus and hollow stem are unusual in the genus.
 
Taxon name: