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The objective of this study was to estimate the dispersal rate in an organism assumed to be confined totree stands with unbroken continuity. We used the lichen-forming ascomycete Cliostomum corrugatum,which is largely confined to old oak stands. Five populations, with pairwise distances ranging from 6.5to 83 km, were sampled in Östergötland, south-eastern Sweden. DNA sequence data from an intron inthe small subunit nuclear ribosomal RNA gene was obtained from 85 samples. Nearly all molecular variance(99.6%) was found within populations and there were no signs of isolation-by-distance. The absolutenumber of immigrants per population per generation (estimated to 30 years), inferred by BayesianMCMC, was found to be between 1 and 5. Altogether, evidence suggests abundant gene flow in the historyof our sample. A simulation procedure demonstrated that we cannot know whether effective dispersal isongoing or if it ceased at the time when oaks started to decrease dramatically around 400 years BP. However,a scenario where effective dispersal ceased already at the time when the postglacial reinvasion ofoak had reached the region around 6000 years BP is unlikely. Vegetation history suggests that the habitatof C. corrugatum was patchily distributed in the landscape since the early Holocene. Combined with thehigh dispersal rate estimate, this suggests that the species has been successful at frequently crossing distancesof at least several kilometres and possibly that it has primarily been limited by the availability ofhabitat rather than by dispersal.

Many lichen fungi form symbioses with filamentous Nostoc cyanobacteria, which cause the lichen toswell and become extremely gelatinous when moist. Within the Lecanoromycetes, such gelatinous lichens are today mainly classified in the Collemataceae (Peltigerales, Ascomycota). We performed Bayesian MCMC, maximum likelihood, and maximum parsimony analyses of three independent markers(mtSSU rDNA, nuLSU rDNA, and RPB1), to improve our understanding of the phylogeny and classification in the Peltigerales, as well as the evolution of morphological characters that have been used for classification purposes in this group. The Collemataceae and the non-gelatinous Pannariaceae are paraphyleticbut can be re-circumscribed as monophyletic if Leciophysma, Physma, Ramalodium and Staurolemma are transferred to the Pannariaceae. The gelatinous taxa transferred to the Pannariaceae deviate from other Collemataceae in having simple ascospores, and several also have a ring-shaped exciple as in other Pannariaceae, rather than the disc-shaped exciple found in the typical Collemataceae. Both Collema and Leptogium are non-monophyletic. The re-circumscribed Collemataceae shares a distinct ascus type withthe sister group Placynthiaceae and the Coccocarpiaceae, whereas Pannariaceae includes a variety of structures. All Pannariaceae have one-celled ascospores, whereas all Collemataceae have two- or multi-celled spores. Reconstructions of the number of character state transformations in exciple structure, thallus gelatinosity, and ascus apex structure indicate that the number of transformations is distinctly higher than the minimum possible. Most state transformations in the exciple took place from aring-shaped to a disc-shaped exciple. Depending on the reconstruction method, most or all transformationsin thallus structure took place from a non-gelatinous to a gelatinous thallus. Gains and losses of internal structures in the ascus apex account for all or a vast majority of the number of transfor

Bacidia rosellizans S. Ekman is described as new to science. Morphologically, the newspecies is similar to the type species of the genus, B. rosella (Pers.) De Not., particularly in the pale pinkand pigment-deficient apothecia and in having the proper exciple and upper part of the hymeniuminspersed with minute crystals that consist at least partly of atranorin. Bacidia rosellizans, however,differs in having a thin whitish thallus, smaller apothecia and a thinner apothecial margin, a dense layerof crystals along the excipular rim, shorter and narrower ascospores with fewer septa, and septateconidia. Whereas B. rosella is a species occurring in the nemoral zone of Europe and possiblynorthernmost Africa and parts of Asia (but not North America), B. rosellizans is found mainly onPopulus and Salix in taiga. This species is currently known from Sweden, Russia, Canada and the USA.It was erroneously treated as Bacidia rosella in a monograph of North American corticolous species ofBacidia and Bacidina by Ekman (in Opera Botanica 127, 1996).

Recent surveys of the inland rain forests of British Columbia and adjacent regions have brought to light an unexpectedly rich epiphytic lichen flora, including several species apparently new to science. In the first of a series of papers, we describe eight species discovered during these surveys as new: Absconditella amabilis T. Sprib. (Ostropales), Bacidina contecta S. Ekman & T. Sprib., Biatora aureolepra T. Sprib. & Tonsberg, Biatora ligni-mollis T. Sprib. & Printzen (all Lecanorales), Collema coniophilum Goward (Peltigerales), Pertusaria diluta C. Björk, G. Thor & T. Wheeler (Pertusariales), Schaereria brunnea C. Björk, T. Sprib. & T. Wheeler (Ostropomycetidae incertae sedis) and Scoliciosporum abietinum T. Sprib. (Lecanorales). We also call attention to a ninth species, Bacidina sp. A, a poorly known and possibly undescribed colonizer of moribund cyanolichens. A majority of the above species appear to be confined to old-growth forests, while two (Biatora ligni-mollis and Schaereria brunnea) are currently known only from "antique" forests older than about 500 years. Many additional undescribed epiphytic lichens are known from inland rain forests, underscoring the need for further baseline biodiversity research in light of its ongoing disappearance as a result of resource extraction. In addition to the eight new species, we report Absconditella celata as new to North America, Absconditella lignicola as new to Canada and Montana, Bacidina chloroticula as new to British Columbia and Gyalideopsis piceicola as new to Montana.

In this paper, we discuss a part of participatory culture that so far has not received much attention in the academic world; it is the writing and reading of game fan fiction. The focus in this paper is on fan fiction, based on three different games that represent three different game genres: Tetris, StarCraft and Dreamfall: The Longest Journey. The aim is to advance our understanding of how players experience and understand the game environment, and promote further research interest in fan fiction based on computer games. We do this by discussing narrative elements in the above mentioned computer games, and the fan fiction that is based on them.

The molecular phylogeny of the lichen genus Lecaniawas investigated using nucleotide sequences from the mt-SSU rRNA, the ITS region of the nu-rDNA, and the RNA polymerase II second largest subunit. Forty-six species representing Lecania and other genera likely to influence the phylogeny were included in the study. Phylogenetic reconstructions were carried out using Bayesian inference, ML, and MP approaches. Lecania, as traditionally circumscribed, is not a monophyletic genus. However, a monophyletic group containing a large number of Lecania species, including the type species L. fuscella, was discovered in the analysis, and recognition of Lecania sensu stricto is suggested. L. baeomma, L. glauca, L. gerlachei, L. brialmontii, L. racovitzae, L. hyalina (alias Biatora globulosa), L. chlorotiza, L. naegelii, and L. furfuracea do not belong in Lecania s. str., although the latter two are closely related to Lecania s. str. Representatives of the genus Bilimbia form a well-supported group, as does the ‘Thamnolecania’ group containing the Antarctic ‘Lecania’ species, L. gerlachei, L. brialmontii, and L. racovitzae. An alternative to recognizing these two genera would be a wider circumscription of Bilimbia to include the ‘Thamnolecania’ group as well as affiliated taxa.

In order to examine genetic variation and population structure of the widespread lichen-forming ascomycete Xanthoria parietina from similar habitats, but different sites in Scandinavia, we investigated seven populations in Scania, southernmost Sweden, and compared the results with a corresponding study on Storfosna, central Norway. Sequence variations of the nuclear ribosomal DNA were used as molecular markers, for both a part of the IGS region and the complete ITSI-5.8S-ITS2 region. The amount of genetic variability observed was comparable in the two investigations. Divergence between populations in different habitats found in the previous study was also present in this study. Xanthoria parietina is genetically differentiated between habitats with no evidence of restricted gene flow between populations in the same habitat at the present spatial scale, at least at sites along the coast of Scandinavia. Differentiation between habitats is considerable at both study sites, which we attribute to restricted gene flow between habitats, i.e. habitat isolation.

Stockholm/Stehag [tillverkningsort]

The aim with this study is to determine genetic variation, dispersal potential and the migration history to Sweden since the last glaciation of the rare lichen Cliostomum corrugatum, a crustose epiphytic lichen with a grey greenish thallus,conspicuous light yellow to light brown apothecia and black pycnidia. Collections were made in January and February in 2005 at five sites in Östergötland, Sweden. The most frequent common habitat for Cliostomum corrugatumis on Quercus and sometimes also on other deciduous trees for example Ulmus and Fraxinus. On the tree trunk it is the rough bark it prefers and the flat terminal parts of the bark structure and not on the sides of the cracks. The main distribution of Cliostomum corrugatum is in Europe but a satellite population has been found on the west coast of North American in British Columbia. It is red listed in Sweden, with the status near threatened. Three sequences SSUintron, IGS and ITS were studied and the two latter appear to lack genetic variation. A total of 85 sequences with a length of 614 base pairs were studied of a rRNA SSU intron. Eleven haplotypes were detected, two was common 46 and 30 in numbers respectively and was present on all five localities the other nine were detected only once each. The two common haplotypes are in the centre of a rooted net work and the rare in the periphery. Cliostomum corrugatum does not seem to have problem with its dispersal. The limiting factor seems to be the occurrence big oaks. In the studied area the smallest tree trunk diameter that Cliostomum corrugatum was found on is 0,65 metre. The tree with the largest diameter in the research area is 1,65 metre. A tree that is 0,65 metre in diameter is at least 100 years old. Oaks of this age are scarce and this is one of the reasons for the rareness of Cliostomum corrugatum. When Cliostomum corrugatum colonized Sweden after the last ice age, all eleven haplotypes may already have existed. However, it is possible, that some haplotype