Sphagnum tundrae (sect. Squarrosa) is reported new to arctic North America and eastern Russia. This species was recently described from Svalbard, arctic Norway, and has until now not been reported from other areas. It is argued, that it reached Svalbard in early/middle Holocene by long distance chance dispersal through icerafting diaspores following main Arctic Ocean currents from arctic Eurasian sources. Supposedly closely related to S. teres, the distinctness of the gene pools of those two species is evaluated through isozyme analysis of a mixed population, as well as small samples from three other S. tundrae sites and two sites with S. teres populations from Svalbard. Fifteen putative enzyme loci were screened. Very little intraspecific genetic diversity was detected. Sphagnum tundrae was monomorphic throughout the four populations studied, whereas S. teres had three haplotypes. The mean genetic identity (Nei 1978) among populations of S. tundrae and S. teres in this sample from Svalbard was calculated as 0.525, which is in concordance with values obtained among other Sphagnum species. Sphagnum mirum is described as a new species from subarctic Alaska, differing in essential morphological characteristics from the related S. teres and S. tundrae. Morphological variation in mixed stands of S. mirum and S. teres from the type locality clearly demonstrates its specific distinctness in qualitative as well as quantitative characteristics.

Intra-annual growth patterns of Racomitrium lanuginosum, Pleurozium schreberi, Sphagnum austinii, Sphagnum fuscum, Sphagnum rubellum, Sphagnum papillosum, Sphagnum lindbergii, Sphagnum tenellum, and Sphagnum pacificum were studied in relation to local precipitation and temperature in a sloping open peatland on the hypermaritime north coast of British Columbia. The growth of mosses was strongly correlated with precipitation and less with temperature. A temperature effect on growth was suggested by the emphasized correlation between growth and a combination of precipitation and temperature. Temperature thresholds for Sphagnum spp. were estimated to be lower than those for P. schreberi and R. lanuginosum. Growth rates of hummock Sphagnum spp. were lower and the seasonal growth pattern was less variable than those of hollow and lawn Sphagnum spp. Despite low vertical growth rates, hummock Sphagnum spp. had higher productivity than hollow and lawn Sphagnum spp. Winter-growth in this hypermaritime region appears to be important.

Ophioparma juniperiicola, a new lignicolous species, is described from eastern Spain. It is closely related with O. rubricosa by the appearance of thallus and apothecia, and the presence of divaricatic and usnic acids. The outstanding differences are in spore size and shape and the pycnospore width. Ophioparma juniperiicola is a lignicolous species with granular thallus–often reseambling isidia–and three septate ascospores, with average and size interval do not overlap with other species in the genus. A key of Ophioparma species is presented.

Arctoa fulvella (Dicks.) Bruch & Schimp. is reported for the first time in the Southern Hemisphere from Isla Navarino (Chile) in the Tierra del Fuego archipelago. The species (and genus) is established as another bipolar moss disjunct and its global range is reviewed and mapped. Bipolar disjuncts in mosses are placed into two categories: taxa with intermediate stations in tropical and subtropical regions and those without intermediate occurrences in intertropical regions. Trans-American bipolar mosses belonging to each of these two groups are listed.

1) Miriquidica leucophaeoides (syn. Lecidea leucophaeoides Nyl.) is proposed as a new combination. 2) The following taxa are synonyms (correct names in parenthesis): Lecidea aglaeida Nyl. (= Calvitimela aglaea), Lecidea cheiloplaca Vain. (= Miriquidica deusta), Lecidea chlorophanoides H.Magn. in Malme (= Candelariella vitellina), Lecidea confluens f. refluens Vain. (= Lecidea confluens), Lecidea declinans f. subsculptella Nyl. (= Lecidea lapicida var. lapicida), Lecidea konyamensis Nyl. (= Miriquidica leucophaeoides), Lecidea lenensis Oxner (= Calvitimela aglaea), Lecidea lugubrior Nyl. (= Clauzadeana macula), Lecidea melapsepha Nyl. (= Cecidonia xenophana), Lecidea reducens Vain. (= Lecidea lapicida var. lapicida), Lecidea subfumosa (Arnold) Zwackh f. melanocarpa Vain. (= Rhizocarpon polycarpum), Lecidea subfumosa f. poliocarpa Vain. (= Lecidea atrobrunnea: chemorace 0), Lecidea subtristiuscula Nyl. (= Miriquidica leucophaeoides). 3) Lectotypes were chosen for Lecidea konyamensis Nyl., Lecidea lygotropa Nyl., Lecidea reducens Vain., Lecidea subfumosa f. melanocarpa Vain., Lecidea subfumosa f. poliocarpa Vain., Lecidea subtristiuscula Nyl. 4) New records are documented for: Cecidonia umbonella (new to Beringian Alaska), Cecidonia xenophana (new to Asia), Lecidea confluentula (new to Asia), Lecidea ecrustacea (new to Beringian Alaska), Lecidea lapicida (new to Kamchatka), Lecidea paupercula (new to Kamchatka and to Beringian Alaska), Lecidea plana (new to Alaska and Kamchatka), Lecidea swartzioidea (new to Kamchatka), Lecidea umbonata (new to Chukotka), Miriquidica deusta (new to Alaska), Miriquidica leucophaeoides (new to Alaska and Taimyr), Rimularia impavida (new to Alaska), and Schaereria fuscocinerea (new to mainland Alaska).

The new species, L. demosthenesii Lumbsch & Messuti, L. guderleyi Lumbsch & Messuti, L. pallidochlorina Nash, Ryan & Lumbsch, L. pseudachroa Lumbsch & Messuti, and L. ryanii Nash & Lumbsch, are described. Descriptions for L. carneolutescens and L. orizabana are provided. These overlooked species are new to the U.S.A.

Pyrrhospora gowardiana Spribille & Hauck is described as a new crustose lichen with red apothecia growing primarily on twigs and bark of Larix, Pinus, and Pseudotsuga in montane western North America. It differs from the widespread and circumboreal P. cinnabarina (Sommerf.) Choisy in absence of soredia; verruculose to verrucose, grayish thallus; larger, more strongly convex apothecia; and occurrence in dry, exposed habitats. The species is furthermore the first representative of its genus from which pycnidia have been reported.

Bacidia nivalis, known only from the Pacific Northwest of North America, is transferred to Stereocaulon as S. nivale. This is the first report of a crustose species of Stereocaulon from North America.

Schistidium is the richest moss genus in the Antarctic consisting of twelve species, one of which, S. deceptionense Ochyra, Bednarek-Ochyra, & Lewis Smith, is here described as new to science from the volcanic Deception Island in the South Shetland Islands archipelago in the northern maritime Antarctic. Its most peculiar diagnostic characters are strongly thickened walls of the exothecial cells; small, cupulate, and pachydermous capsules; and sinuouse laminal cells. In these features the new species shows the closest affinity to S. urnulaceum (Müll. Hal.) B. G. Bell, a South Georgian-Antarctic endemic, from which it can be distinguished by sharply keeled leaves, stout costae that are semi-terete in transverse section and strongly convex dorsally, bistratose leaf margins in 1–2 rows of cells forming bulging thickenings in the distal portion, shorter laminal cells, and larger spores. The relationships of S. deceptionense are discussed and the species is considered to belong to the Confertum group with which it shares pellucid alar region of the hyaline cells with the transverse walls much thicker than the longitudinal walls, narrow upper laminal cells, irregular and mostly strongly perforated peristome teeth, and yellow reaction of the upper leaves and leaf cells with KOH. A key to all species of Schistidium in the Antarctic is given.

Didymodon revolutus (Cardot) R. S. Williams, currently known from America, is reported for the first time from Asia (Yemen). The species is lectotypified, described, and illustrated. A map showing the pantropical distribution of this species with stations in southwestern and central U.S.A. is provided.

Fissidens cagoui Frank Müll., Pursell & Brugg.-Nann., in section Amblyothallia, is described and illustrated. Fissidens pseudopallidus I. G. Stone, hitherto known only from Queensland, Australia, is reported new to the moss flora of New Caledonia. Also, F. rigidulus Hook. f. & Wilson is newly recorded for the island. Records for five other species are appended.

Cellulose-acetate filter disks were found convenient for the cultivation of lichen mycobionts and artificial re-synthesis of lichens, and using this method of culture we tested the effects of acidification on Cladonia cristatella Tuck. Mycobionts subjected to short-term strongly acidic conditions showed decreased formazan production compared to colonies grown at optimal pH 5.0. Disk-supported synthetic lichens grown at pH 3.0 or 5.0 exhibited no significant differences in pigment chemistry or photosynthetic efficiency compared to those at pH 7.0, but all of these parameters changed at pH 1.5. Chlorophyll a integrity significantly decreased under all treatments involving acidified water, with the highest amount of degradation at pH 1.5. At pH 1.5, significantly decreased concentrations of both β-carotene and total carotenoids were observed. A significant decrease in chlorophyll a fluorescence was also shown at pH 1.5.

Bryoria spiralifera Brodo & D. Hawksw and B. pseudocapillaris Brodo & D. Hawksw are two rare maritime lichens that were described from a small number of samples. This study describes the habitat and investigates chemical and morphological differences between the two species in the Picea sitchensis and Pinus contorta var. contorta forests of the Samoa Peninsula, location of the largest known population of B. spiralifera. Bryoria spiralifera is well distributed (100% frequency), and B. pseudocapillaris is less common (10% frequency) in each of the two stand types. Both species co-occur on the same branches, and both species are most abundant in high exposure sites such as forest edges along sand dunes and large canopy gaps. In Pinus contorta var. contorta stands, which tend to have open canopies, these two species are abundant, both in the understory as well as the upper canopy. In Picea sitchensis stands with more closed canopies, these species mostly occupy the upper canopy. Thin layer chromatography and logistic regression support the original hypothesis that B. spiralifera and B. pseudocapillaris are separate species. Thin layer chromatography showed that both species have distinctive, unshared secondary products. A logistic regression model finds several combinations of morphology as strong predictors of identity. Bryoria spiralifera is variable in regards to color and pseudocyphellae, but many have spiraling pseudocyphellae, while B. pseudocapillaris is mostly pale, with long, linear pseudocyphellae.

Four species of lichens are reported as new to South America, namely the cosmopolitan or bipolar Dermatocarpon polyphyllum and Xylographa abietina, and the austral Hypocenomyce australis and H. foveata. The following four taxa are reported for the first time for Argentina: Baeomyces rufus, Cystocoleus ebeneus, Lecanora intricate, and Placynthiella icmalea, and the range of Trapeliopsis granulose is extended to Tierra del Fuego.