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Literature:
 
Page number:48 
Description type:Non-original description 
Description:Hymenochaete dregeana (Berk.) Massee in J. Linn. Soc. Bot. 27: 114 (1890). Plate 14A
Corticium dregeanum Berk. in Hooker's Lond. J. Bot. 5 : 3 (1846). Lopharia dregeana (Berk.) Talbot in Bothalia 6 : 57 (1951).
Irpex dregeana (Berk.) Talbot in Bothalia 6 : 344 (1954).
"Effusum, resupinatum, papyraceum, e matrice separabile ochroleucum supra subtiliter tomentosum; hymenio rimosiusculo glabro papillato. Drège,' n. 9451, c.
South Africa, on bark.
Forming effused ochroleucus somewhat elongated patches, 3-4 inches long, 1,5 inches broad, separable from the matrix, above minutely tomentose; hymenium glabrous, minutely mealy, rather rugged papillose, slightly cracked.
Resembling somewhat Corticium molle but easily distinguished by its thicker flexible substance, which is separable from the matrix."
"Effused, resupinate, papyraceous, separable from the matrix, ochroleucus, subtly tomentose above; hymenium becoming rimose, glabrous, papillate. Drège, n. 9451, c."
Sporophores: consisting of incomplete resupinate portions up to 4,5 x 4,0 cm, with a somewhat undulating pale pinkish-cream hymenial surface, ornamented with a few inconspicuous, low rounded warts, which are easily overlooked; under a lens the surface is seen to be minutely cracked, but this feature is not obvious to the naked eye. Margin distinct. The surface next to the substrate, from which the fungus is easily separable, is whitetomentose. Flesh thin, white. Hyphal structure: monomitic, consisting of densely entwined, thick-walled, hyaline, glassy generative hyphae, up to 8 µm wide. These hyphae which lack clamp-connexions and are constricted at the septa, are more laxly arranged near the substrate. In the region of the hymenium the hyphae are only 2-3 µm wide and either thin or slightly thickwalled. Hymenium thickening, reaching 100 µm in width. Cystidia very abundant, as long, thick-walled, lanceolate or fusiform, densely crowded bodies, 5-9 µm wide, and up to 136 µm long, with encrusted apices. They arise either from the broad thick-walled hyphae of the flesh and curve up into the hymenium, or they may arise at any level within the hymenium itself and project beyond it, many however become buried as the hymenium thickens. Basidia not seen, but these grow up between the cystidia. Spores not seen.
Talbot (1951) published a full account of this species under the name Lopharia dregeana, based on an examination of the type and additional gatherings. He reported basidia as "15,0-26,0 x 3,0-3,5 µm", and spores as "hyaline, smooth, elliptic, 6,5-7,0 x 4,5-5,0 µm". Subsequently he (1954a) transferred the fungus to the genus Irpex Fr., and listed I. vellereus Berk. & Br. from Ceylon in synonymy. Reid (1955) studied the latter and considered that it was possibly distinct from I. dregeana on account of its spore size and narrower cystidia. Later Reid (1963) noted that the correct name for I. vellereus was I. griseo-fuscescens (Reich.) Reid. In any event, I. dregeana and I. griseo-fuscescens are very closely related species, and are best left in the genus Irpex.
 
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