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Page number:110 
Description type:Non-original description 
Description:Trechispora nivea (Pers.) K. H. Larss. comb. nov. (Figs 7-9)
Odontia nivea Pers., Neues Mag. Bot. (Ed. Römer) p. 110 (1794). - Hydnum niveum (Pers.) Pers., Syn. Meth. Fung. p. 563 (1801). -Hydnum niveum (Pers.: Fr) Pers., Syst. mycol. 1: 419-20 (1821).Basidiomata resupinate, effuse, easily separable from the substratum but not pellicular, soft and fragile, white to light ochraceous. Hymenophore densely hydnoid; spines narrow, nearly cylindrical, with blunt and somewhat tufted apices, up to 1 mm long, initially forming ridges and flattened veins giving young areas of the basidioma a subporoid appearance; smooth areas fertile, arachnoid to byssoid. Margin thinning out, often forming radiating hyphal mats and cord-like structures, white. Hyphal system monomitic; all septa with clamps. Cords with straight, anastomosing, slightly thick-walled, 1.5-3 µm wide hyphae, with ampullate septa up to 6 µm wide. Subiculum with hyphae similar to those in the cords, often provided with small bladders, projections or irregular wall thickenings resulting from swelling of the hyphal wall and from the initiation of crystal-chambers, usually encrusted. Trama in spines with mainly straight, frequently branching, slightly thick-walled hyphae, mainly 3 µm wide, often with irregular wall thickness, usually encrusted. Subhymenium with short-celled, richly branched, cylindrical to slightly inflated or irregular, thin-walled, mainly 3 µm wide hyphae. Basidia cylindrical with a slight median constriction, 8-15 x 4-5 µm, with four, rather straight sterigmata up to 3 µm long and with a basal clamp. Basidiospores subglobose to broadly ellipsoidal, ventrally flattened, verrucose with low to medium-sized warts, 3-4 x 2.5-3.5 µm inclusive of the up to 0.3 µm high warts, not or only weakly cyanophilous. Crystals usually present, bipyramidic, aggregated.
Habitat and ecology. T. nivea grows on dead wood from a variety of lignoses. The following
genera are noted as substrate: Abies, Acer Alnus, Betula, Buxus, Coffea, Fagus, Laurus, Musanga, Picea, Pinus, Populus, Quercus, Raphia, Sabal, Sorbus, Tilia, and Ulmus. Some finds are made on dead basidiomata of polypores, and on mosses. In Northern Europe T. nivea seems to favour deciduous forests and wood from angiosperm species.
Distribution. This species is the most widespread of any Trechispora. Its distribution is world-wide and covers tropical as well as temperate, nemoral and boreal regions extending into the subalpine birch forest of northernmost Sweden.
T. nivea has characteristics very close to those of T. mollusca (Pers.: Fr.) Liberta. The main difference is a hydnoid instead of a poroid hymenophore. The two species also show different distribution patterns. Whether these differences justify the separation of two species cannot be solved in this study.

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