We describe the morphology and ultrastructure of mature spores of four epiphytic pleurocarpous mosses from the Canary Islands laurel forest: Leucodon canariensis (Brid.) Schwägr., Cryptoleptodon longisetus (Mont.) Enroth., Neckera cephalonica Jur. & Unger., and N. intermedia Brid. The two Neckera species are strictly isosporic, while the capsules of L. canariensis contain viable spores of two classes—uni- or multicellular, medium-sized (26–48 µm) spores; and multicellular, large (50–94 µm) spores. Also in C. longisetus, two different kinds of viable spores are produced in the capsules—unicellular, small spores (11–24 µm) and medium-sized (26–35 µm) spores. These observations suggest anisospory for both species. Intracapsular spore germination is observed in three species, but not in N. cephalonica. Spore wall stratification of the four species follows the typical pattern for mosses—perine, exine and intine. The ornamentation pattern is uncharacteristic, with perine variously papillose. All spores are inaperturate. The cytoplasm shows abundant lipid-like inclusions and chloroplasts with well-developed thylakoids. The taxonomic significance of the spore characteristics is discussed.

Research concerning ecological relationships between corticolous lichens and substrate factors in Cuba is limited. This study aims to determine the variation of composition, richness, frequency and cover area of corticolous lichens of the montane rainforest of Gran Piedra in Cuba related to physical and chemical substrate factors, including diameter of the trunk, roughness, per cent moisture, pH, and concentration of bark phenols. In addition, lichen-phorophyte specificity of the tree species Gomidesia lindeniana, Coccoloba wrightii, Clusia tetrastigma, Dendropanax arboreus and Brunellia comocladifolia was determined. On 51 sampled phorophyte trees, 53 lichen species were found, 19 of which are new records to Cuba. Canonical Correspondence Analysis showed a segregation pattern in the species composition due to diameter of the trunk, pH and phenol concentration of the bark. Lichen-phorophyte specificity was almost absent, with only two lichen species, Ocellularia terebrata and Chapsa neei, showing a significant association with Brunellia comocladifolia.

A new species with a corticated brown thallus, Sarcogyne mitziae, is described from biotic soil crusts in California, Idaho, and Washington. The species is considered rare and occurs in habitat that is threatened by anthropogenic factors such as development, grazing, and fire, throughout western North America. Seventeen species of Sarcogyne are currently recognized for North America.

Two new genera, Myriochapsa M. Cáceres, Lücking & Lumbsch and Nitidochapsa Parnmen, Lücking & Lumbsch, are introduced for the species Chapsa psoromica and C. leprieurii, which are not genuine Chapsa species but related to Myriotrema and Ocellularia, respectively. The following two new combinations are proposed: Myriochapsa psoromica (M. Cáceres, Santos de Jesus & Santos Vieira) M. Cáceres, Lücking & Lumbsch comb. nov., and Nitidochapsa leprieurii (Mont.) Parnmen, Lücking & Lumbsch comb. nov. Myriochapsa psoromica is morphologically and chemically similar to Myriotrema species but differs in the wider apothecial pore with fissured-lobulated margin; it is known only from the western Amazon (Brazil: Rondônia). Nitidochapsa leprieurii is characterized by a brown, nitidous thallus and Chapsa-like apothecia with wide, pruinose disc and lobulate to recurved, felty, white margin; it has brown ascospores and lacks secondary compounds. The species is pantropical. The interpretation of phenotype characters in a molecular phylogenetic framework is discussed.

Evidence for naturally occurring programmed cell death in Marchantia polymorpha tuberculate rhizoids as a function of age is described. Membrane degradation and DNA fragmentation, two major events that occur during programmed cell death, are detected and quantified using Trypan Blue staining and the TUNEL Assay. Membrane permeability and DNA fragmentation both increase as the tuberculate rhizoids aged. Spermine suppressed this response; hydrogen peroxide accelerated it. This research has advanced the study of PCD by demonstrating that nutrient recycling of the thallus and tuberculate rhizoids of Marchantia polymorpha are interrelated.

The monotypic genus Schroeterella including its species S. zygodonta are known only from thetype collection from Bolivia; we now report a new record from Brazil. Also a new species of Schroeterella from Ecuador is here described. Both species can be differentiated by the shape and size of the capsule and seta length. Schroeterella is very difficult to recognize when sterile, so it is likely to be misidentified.

Fungal selectivity (range of potential partners) for algal symbionts has been found to vary inlichen associations. Although a large number of studies have focused on the taxonomy and evolution of fungi in the speciose parmelioid clade (Parmeliaceae, Ascomycota), fungal-algal interactions in this ecologically and evolutionarily diverse group remain largely unexplored. In this study we investigated the algal symbionts of Xanthoparmelia fungi in western North America. We generated sequence data from a total of 58 rock shield lichens (Xanthoparmelia fungi Trebouxia algae) collected across three sites in a subalpine community in southern Utah, USA. We explored the role of substrates, secondary metabolite variation, phenotype-based Xanthoparmelia species, mycobiont genetic population clusters, and site-specific differences in structuring assemblages of algae. Our results indicate that Xanthoparmelia fungi associate with a broad range of Trebouxia lineages in a local, subalpine habitat. Most algae sampled form part of the diverse Trebouxia ‘arboricola/gigantea’ clade, while a small number of algae from outside of this clade were also found to associate with the Xanthoparmelia species investigated here. Our results also revealed multiple Trebouxia lineages within the T. ‘arboricola/gigantea’ clade that have not been previously recognized. Furthermore, accumulation curves suggested that additional algal diversity in rock shield lichen communities in the sampled subalpine habitat may be recovered with increased sampling. Overall, we found no clear association of algal clades with traditional phenotype-based Xanthoparmelia species, mycobiont genetic population clusters, distinct extrolites, or substrates. However, our data revealed significant genetic structuring of Trebouxia communities in separate subalpine meadow areas in a relatively homogeneous subalpine community. Significant site-specific differences in Trebouxia diversity in rock shield lichen communities and low selectivity suggest that photobiont flexibility may play an important role in overall successful colonization of rock shield lichens across a wide array of habitats in western North America.

The new genus Austroroccella Tehler & Ertz is described to incorporate one species A. gayana(Mont.) Tehler & Ertz comb. nov. ( = Roccella gayana Mont.). Austroroccella gayana is very similar to the fruticose species in Roccellina Darb., as well as to many saxicolous species in the fruticose genus Roccella DC., but differs from these genera by the epruinose dark or black discs and the sole presence of roccellic acid. Molecular data places it in an isolated position with a long branch in the family Roccellaceae in a highly supported clade including the genera Dendrographa Darb., Syncesia Taylor and Roccellina.

As part of a larger systematic and taxonomic revision of the genus Sticta in the northern Andes, several species were discovered forming green algal and cyanobacterial photosymbiodemes, seven of which are new to science and are described here—S. lobarioides Moncada & Coca, S. macrothallina Moncada & Coca, S. neopulmonarioides Moncada & Coca, S. phyllidiokunthii Moncada & Lücking, S. pseudolobaria Moncada & Coca, S. pulmonarioides Moncada & Coca, and S. tatamana Moncada & Coca. All species are discussed and illustrated, and a key to species with Lobaria pulmonaria gross morphology is given.