Volume 42(1), 2002

Ecology and decay pattern of Phellinus robustus in old-growth Quercus robur
Stellan Sunhede, Rimvydas Vasiliauskas
Karstenia 42: 1-11.
The biology of Phellinus robustus (P. Karst.) Bourdot & Galzin (Hymenochaetales) was studied on Quercus robur L. in Lithuania, based on 677 host trees. Basidiocarp occurrence related to the diameter of the oaks and spatial distribution of basidiocarps on the trees are presented. Distribution of decay in eight sectioned, 110 –175 year-old oaks showed one to three 0.1–5.8 m long, vertically separated rot columns. Vegetative compatibility tests indicated that each rot column was made up of a single genet of P. robustus and that the rot columns in the eight studied trees represented different genets. Infection routes, parasitic and saprotrophic behaviour, age of basidiocarps, forestry and biodiversity aspects are discussed. Illustrations show geographical distribution of the species in Lithuania, distribution of infected oaks in an old oak stand, frequency of infected trees related to diameter of the trunks, and distribution of decay in longitudinal and cross sections of trunks. Colour photos show distribution of white rot in the substrate, aerial mycelium on sectioned wood, and confrontation tests between cultivated mycelia of the same and different genets.

The occurrence of myxomycetes on different decay stages of trunks of Picea abies, Pinus sylvestris and Betula spp. in a small oldgrowth forest in southern Finland
Tarja Ukkola
Karstenia 42: 13-22.
The occurrence of myxomycetes was studied on fallen trunks of Picea abies, Pinus sylvestris, and Betula spp. (B. pendula and B. pubescens) in a small oldgrowth forest in southern Finland in May 1998 – September 1999. The study site is located in Luukkaa Recreation Area, and was left in pristine state in 1966. The sample trunks were chosen to represent different stages of decomposition and checked every second or fourth week in all for 17 times. A total of 325 myxomycete specimens representing 44 taxa in 16 genera were observed. Four taxa, Comatricha pulchella var. fusca, Lycogala exiguum, Licea cf. pusilla, and Physarum bethelii are new records to Finland. During the study, myxomycetes were most abundant on decomposing trunks of Betula spp. (123 specimens), especially on well-decayed trunks. The species diversity was about the same on all studied tree species: 27 taxa were recorded on P. abies and P. sylvestris, and 22 on Betula spp. The largest diversity was on two pine trunks with fairly soft wood (a total of 19 taxa). The common myxomycetes, Ceratiomyxa fruticulosa and Lycogala epidendrum, represent generalists in this study, being abundant and present at nearly all decay stages of all studied tree species. Leocarpus fragilis and Tubifera ferruginosa are examples of species that preferred well-decayed wood, and Stemonitopsis reticulata and S. typhina were found only on hard to fairly hard wood. The peak of the number of taxa and abundance of myxomycetes occurred from July through to September.

Lepista polygonarum and Prunulus lammiensis, two new combinations in the Agaricales
Harri Harmaja
Karstenia 42: 23-25.
Clitocybe polygonarum Laursen, O.K. Miller & H.E. Bigelow (Tricholomataceae) from arctic Alaska is transferred to Lepista (Fr.) W.G. Sm. as Lepista polygonarum (Laursen, O.K. Miller & H.E. Bigelow) Harmaja, comb. nov. The taxonomy of the species group that includes L. polygonarum is briefly discussed. The name Tricholoma multiforme has been incorrectly attributed to Romell as a new species. It is not synonymous with L. polygonarum. The nomenclature of Agaricus multiformis Schaeff. and Cortinarius multiformis Fr. is clarified. Mycena lammiensis Harmaja (Mycenaceae) is transferred to Prunulus Murrill, a segregate genus comprising species around M. pura (Pers. : Fr.) Kumm., as Prunulus lammiensis (Harmaja) Harmaja.

Caloscyphaceae, a new family of the Pezizales
Harri Harmaja
Karstenia 42: 27-28.
The new family Caloscyphaceae Harmaja is described for Caloscypha Boud. (Ascomycetes, Pezizales). The genus is monotypic, only comprising C. fulgens (Pers.: Fr.) Boud. Characters believed to be diagnostic of the family are treated, some of them being cited from the literature, others having been studied personally.