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Page number:1239 
Remarks (public):The fruitbodies of R. confluens are conspicuously hygrophanous which gives the hymenium during wet conditions a dark, often blueish or violaceous colour. This is one of the reasons that make the species seem very variable. The micromorphological variation concerns mainly the spore shape, from ellipsoid to subglobose.
This makes the limit towards R. rickii (Bres.) M.P. Christ. (Corticium rickii Bres. ex Rick, Oesterr. bot. Zeitschr. 48 p. 136, 1898) uncertain, but so far as we can see all the Nordic material belongs to R. confluens. R. rickii may be a species of its own with a more southern distribution but it is also possible that it only represents one extreme in the spore variation of R. confluens. Corticium cremoricolor Berk. & Curt., Grey. 1 p. 180, 1873, with more oblong spores, may be the other extreme in an unbroken series. Only fertility tests between these three taxa can solve this problem.
Description type:Non-original description 
Description:Radulomyces confluens (Fr.) M.P. Christ., loc. cit. - Thelephora confluens Fr., Syst. mycol. I p. 447, 1821.
Fruitbody resupinate, closely adnate, effused or orbicular-confluent, varying in size from small to quite large, ab. 0.1-0.5 mm thick, when wet watery ceraceous and hygrophanous, greyish, often with a rosaceous or violaceous tint, on drying changing to whitish, greyish or pale buff, more or less tuberculate in the wet state, smoothing on drying; margin in the growing fruitbody fimbriate, then fertile throughout. Normally turning yellow in KOH.
Hyphal system monomitic, all hyphae with clamps, those of the subhymenium 1-3 µm wide, thin-walled and richly branched, those of the subiculum mainly parallel with the substrate, sparsely branchec with thin or thickened walls, ab. 3 µm wide.
Cystidia none. Simple or somewhat branched hyphae often seen, but they are in no way differentiated as dendrohyphidia.
Basidia clavate, sinuose, 35-55 x 6-9 µm, with numerous oil-drops, 4 sterigmata and basal clamp.
Spores ellipsoid-subglobose, 8-12 x 6.5-9 µm, oily and granular, walls smooth, slightly thickened in the mature spores, non-amyloid, non-cyanophilous.
Habitat. On bark and decayed wood of fallen or hanging branches, on logs and stumps, esp. of deciduous tree but in suitable localities also on conifers. It seems to favour humid conditions and is especially common near water e.g. in the Alnus zone along the N. coast of Sweden. It is also a characteristic species in parks and gardens, where it grows on dead branches of cultivated bushes and hedges. It is remarkably common also in the subalpine deciduous forest, e.g. in Abisko nat. park in N. Lapland.
Distribution. Very common in the southern parts of the area, less common northwards but evidently occurring in suitable localities in the whole of N. Europe and is one of the most common species of Corticiaceae.
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