Erythricium laetum (P. Karst.) J. Erikss. & Hjortstam

Description type: Non-original description 
Erythricium laetum (Karst.) Erikss. & Hjortst. Sv. bot. tidskr. 64:166; Hyphoderma laetum Karst., Rev. myc. 11 p. 206, 1889. Fruitbody resupinate, loosely attached to the substrate, smooth at least when dry, in the fresh state often irregularly wrinkled, soft and almost athelioid when young, with age membranaceous, when dried brittle; hymenium bright rose red, fading in the herbarium and at last loosing its colour totally; margin sterile and white, more or less filamentous. Hyphal system monomitic but hyphae varying in nature in different parts of the fruitbody. In the subhymenium, resulting from the thickening of the hymenium, the hyphae are thinwalled, 2,5-3 µm wide, densely interwoven into a ceraceous context. The rest of the hyphae, forming the main part of the fruitbody, are wide (to 10 or even 15 µm in diam.), short-celled and branched into a loose context. The walls of these hyphae are somewhat thickened. Still more so are the straight hyphae that penetrate the context and are mainly found in the margin and next to the substrate. These hyphae are ab. 4-9 µm wide, with sparse septa and ramifications. The development of the fruitbody seems in most cases to start from such straight hyphae. Clamps are lacking throughout. Anastomoses are frequent in all parts of the context. Cystidia none. Basidia varying in shape, clavate, sinuose or somewhat constricted, often basally widened to a suburniform shape, with 4 curved sterigmata, 35-50 x 8-12 µm. A few basidia are seen with apically swollen sterigmata. Spores mainly ellipsoid, but varying in shape (ovoid to oblong), with thickened walls and conspicuous apiculus, 11-13 (-15) x 6-7,5 µm. Spore wall cyanophilous (light blue in cotton-blue, whole spore red in phase contrast). The colour of the living spore is probably red. Habitat. E. laetum belongs to the rich, moist biotopes with deciduous trees and herbs on mouldy soil. It is mainly found in the late autumn, winter, and spring. Several collections are made in the late spring. Summertime the fruitbodies dry up and disappear. The substrate is decayed wood and branches of deciduous trees but the fruitbodies often grow out on dead leaves, wet soil a.s.o. Wintertime living and apparently active fruitbodies can be found under snow-cover.