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 Add this item to the list   Duportella sphaerospora sp. nov. Text-fig. 3.
Description type:Original description 
Description:Duportella sphaerospora sp. nov. Text-fig. 3.
Hymenophore resupinate, annual, ceraceous, adnate, at first developing as scattered orbicular colonies 2-10 mm diameter, merging to form linear areas to 6 x 3 cm; hymeniaI surface pallid buff, dingy greyish-brown, or pallid ochre, rugulose, at length deeply areolately creviced; margins thinning out, free or adnate, concolorous. Context isabelline or tan, 80-250 µm thick, composed of a narrow intermediate layer of intertwined hyphae from which arises a vertical palisade of pseudosetae; hyphal system dimitic; skeletal hyphae 3-5 µm diameter, walls to 1 µm thick, dingy brown, aseptate, sparingly branched, sometimes slightly inflated in scattered hyphae, staining; generative hyphae 1.5-2 µm diameter, walls 0.25 µm thick, hyaline, branched, septate, with clamp connexions. Hymenial layer a close palisade of basidia, paraphyses, gloeocystidia and pseudosetae. Gloeocystidia clavate, subclavate, or elliptical, 32-48 x 10-14 µm,. walls 0.5 µm thick, hyaline, crowded in the intermediate layer, subhymenium and hymenium. Basidia subclavate, 26-32 x 10-12 µm, 4-spored; sterigmata arcuate, slender, to 10 µm long. Paraphyses subclavate, shorter and narrower than the basidia. Pseudosetae forming a palisade beneath the hymenium when crowded, erect, cylindrical, 4-6 µm diameter, finely verruculose, sometimes submoniliform and occasionally bifid; when projecting apices acute, sometimes bifid, many bearing 1-3 short lateral branchlets, verruculose, hyaline, staining. Spores globose or subglobose, 10-12 µm diameter, or 10-12 x 9-10 µm, walls smooth, hyaline, 0.25 µm thick.
HABITAT: Effused on bark of dead trunks and branches.
Nothofagus menziesii (Hook. f.) Oerst. Auckland: Upper Mohaka River, Kaimanawas, 2,000ft, May 1953, J. M. Dingley, type collection, P.D.D. herbarium, No. 12572.
Specific features are the globose or subglobose spores, subclavate or elliptical gloeocystidia; delicate generative hyphae and unusual pseudosetae. In the type collection the hymenium is overmature so that most basidia and paraphyses have collapsed. A few are present, and spores abundant in all sections examined. It would appear that the hymenium is precocious, as in D. fulva, developing at an early stage, later collapsing to be replaced by a palisade of pseudosetae, which is present as a dense coloured palisade in the subhymenium. Pseudosetae are unusual in that they stain deeply in aniline blue, solution, are sometimes bifid at apices, or bear from one to three brief lateral branchlets. All are coated in the apical region with sheaths of fine crystals. Pseudosetae and spores are nonamyloid. Generative hyphae are of appreciably less diameter than those of other species. They are copiously produced and form the bulk of the intermediate layer. Among them lie many pseudosetae, lying at various angles; some are bifid, a few branched, and others exhibit occasional inflated areas. They are finely crystal coated, as are those of the hymenial layer. Gloeocystidia, present also in the extralimital D. tristricula, are crowded in the hymenium, subhymenium and context. They vary appreciably in length and shape, most being subclavate.
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