The lichen genus Lecanactis Körb. in Tasmania comprises six species: L. abietina (Ach.) Körb., which is widespread and pan-temperate; L. latispora Egea & Torrente and L. neozelandica Egea & Torrente, both shared with New Zealand and with the former recorded here from the Auckland Islands for the first time; L. mollis (Stirt.) Frisch & Ertz, shared with Victoria and New Zealand; L. aff. dilleniana (Ach.) Körb., a European species recorded provisionally for Tasmania on the basis of several sterile collections; L. scopulicola Kantvilas, which is described here as new to science and apparently a Tasmanian endemic. This new taxon occurs in rocky underhangs and is characterized by a thick, leprose thallus containing schizopeltic acid, and 3-septate ascospores, 19–30 × 4.5–6 μm. Short descriptions and a discussion of distribution and ecology are given for all species. A key for all 11 Australian species of the genus is provided, including L. subfarinosa (C. Knight) Hellb. and L. tibelliana Egea & Torrente, which are recorded for Australia for the first time, and L. platygraphoides (Müll.Arg.) Zahlbr., a first record for New South Wales. Lecanactis spermatospora Egea & Torrente and L. sulphurea Egea & Torrente are also included.

The lichenicolous ‘heterobasidiomycetes’ belong in the Tremellomycetes (Agaricomycotina) and in the Pucciniomycotina. In this paper, we provide an introduction and review of these lichenicolous taxa, focusing on recent studies and novelties of their classification, phylogeny and evolution. Lichen-inhabiting fungi in the Pucciniomycotina are represented by only a small number of species included in the genera Chionosphaera, Cyphobasidium and Lichenozyma. The phylogenetic position of the lichenicolous representatives of Chionosphaera has, however, never been investigated by molecular methods. Phylogenetic analyses using the nuclear SSU, ITS, and LSU ribosomal DNA markers reveal that the lichenicolous members of Chionosphaera form a monophyletic group in the Pucciniomycotina, distinct from Chionosphaera and outside the Chionosphaeraceae. The new genus Crittendenia is described to accommodate these lichen-inhabiting species. Crittendenia is characterized by minute synnemata-like basidiomata, the presence of clamp connections and aseptate tubular basidia from which 4–7 spores discharge passively, often in groups. Crittendenia, Cyphobasidium and Lichenozyma are the only lichenicolous lineages known so far in the Pucciniomycotina, whereas Chionosphaera does not include any lichenicolous taxa.

The taxonomy of the genus Sticta in Hawaii is reassessed, based on a separately published molecular phylogeny using the fungal barcoding marker ITS. Based on Magnusson and Zahlbruckner's treatment from 1943 and Magnusson's catalogue from 1955, seven species of Sticta and three infraspecific taxa had been reported from the archipelago, all widespread except the putative endemic S. plumbicolor. Here we provide a taxonomic treatment of 13 taxa, 12 species and one subspecies, distinguished in a previous phylogenetic analysis: S. acyphellata, S. andina, S. antoniana, S. emmanueliana, S. flynnii, S. fuliginosa, S. hawaiiensis, S. limbata, S. plumbicolor, S. scabrosa subsp. hawaiiensis, S. smithii, S. tomentosa and S. waikamoi. All taxa are described, discussed and illustrated and a dichotomous key is presented. The implications of revised species taxonomies for studies in other fields such as ecology, ecophysiology, biogeography, biochemistry, and applications such as environmental monitoring are discussed. We also propose a protocol to use Sticta lichens to monitor the environmental health of Hawaiian ecosystems.

There is growing evidence that species and communities are responding to, and will continue to be affected by, climate change. For species at risk, vulnerability can be reduced by ensuring that their habitat is extensive, connected and provides opportunities for dispersal and/or gene flow, facilitating a biological response through migration or adaptation. For woodland epiphytes, vulnerability might also be reduced by ensuring sufficient habitat heterogeneity, so that microhabitats provide suitable local microclimates, even as the larger scale climate continues to change (i.e. microrefugia). This study used fuzzy set ordination to compare bryophyte and lichen epiphyte community composition to a large-scale gradient from an oceanic to a relatively more continental macroclimate. The residuals from this relationship identified microhabitats in which species composition reflected a climate that was more oceanic or more continental than would be expected given the prevailing macroclimate. Comparing these residuals to features that operate at different scales to create the microclimate (landscape, stand and tree-scale), it was possible to identify how one might engineer microrefugia into existing or new woodland, in order to reduce epiphyte vulnerability to climate change. Multimodel inference was used to identify the most important features for consideration, which included local effects such as height on the bole, angle of bole lean and bark water holding capacity, as well as tree species and tree age, and within the landscape, topographic wetness and physical exposure.

Lichens occupy diverse substrates across tremendous ranges of environmental variation. In boreal forests, lichen communities co-occur in ‘strata’ defined by terrestrial or arboreal substrates, but these strata may or may not be interchangeable as bioindicators. Do co-occurring lichen strata have similar community structures and environmental responses? Could one stratum serve as a proxy for the other? We assessed variation in species richness and community compositions between ground-layer versus epiphyte-layer lichen strata in boreal forests and peatlands of interior Alaska. Species richness was lower and more spatially structured in the ground layer than the epiphyte layer. Richness of strata was not correlated. The most compositionally unique ground-layer communities were species-poor but contained regionally rare species not common in other plots. Variation in community compositions (ordination scores) were not congruent between strata (Procrustes congruence < 0.16 on 0–1 scale); the largest departures from congruence occurred where ground layers were species-poor. The best predictors of ground-layer community compositions were hydrological and topographic, whereas epiphytes were most associated with macroclimate and tree abundances. We conclude that lichens on different substrates ‘move in different circles’: compositional gradients did not agree and the environmental gradients most important to each lichen stratum were not the same. The conditions which strongly influence one vegetation stratum may have little bearing upon another. As global changes modify habitats, an incremental change in environment may lead community trajectories to diverge among lichen strata.