Acarospora badiofusca has an irregularly areolate thallus with an uninterrupted algal layer; it is a montane species and occurs in Asia, North America and Europe. Acarospora boulderensis differs from A. badiofusca in having a squamulose thallus, an interrupted algal layer and a higher hymenium. Acarospora boulderensis was considered a synonym of A. badiofusca by North American taxonomists, but is here recognized as a distinct species occurring in North America. Acarospora asperata H. Magn. is revised as a synonym of A. boulderensis. Acarospora irregularis from central Europe (Czech Republic, Hungary and Slovakia), as well as Greece and Italy (Sardinia), was considered a synonym of either A. badiofusca by Weber or of A. nitrophila by Clauzade and Roux. It differs, like A. boulderensis, from A. badiofusca in having a squamulose thallus, an interrupted algal layer and usually a higher hymenium. However, A. irregularis differs from A. boulderensis in having wider hyphal bundles interrupting the algal layer and distinct algal palisades. Acarospora badiofusca var. lepidioides is synonymized with A. irregularis.

Sphagnum and Sphagnum-dominated peatlands have long provided a model for analyses of community structure, and recent work has elucidated the genetic structure of various Sphagnum species in the boreal zone. We report here analyses of genetic variation and population differentiation in a tropical species, S. tumidulum, from Réunion Island. Forty-eight plants (including one sample from Madagascar) were genotyped at 10 microsatellite loci. The species is highly variable on Réunion Island and approximately 22% of the total variation is partitioned among populations. Thirty-one multilocus genotypes could be distinguished and clones represented by more than one gametophyte stem were restricted to individual populations. Our results suggest the occurrence of sexual reproduction on Réunion Island, although sporophytes have not been observed there. Gene flow among most populations appears to be very limited.

Chaenothecopsis australis and C. fennica are reported as new to North America and Microcalicium conversum is reported as new to eastern North America. A key to genera and keys to species that include all 89 known taxa in the Acadian Forest are followed by short narratives highlighting the similarities and differences among them, as well as information on substrates and distribution within and outside the ecoregion.

A recent phylogenetic study by our working group found that the foliose-macrosquamulose basidiolichen genera Cora and Corella contain at least 126 species, over 110 of them as yet undescribed. With this contribution, we begin the herculean task to formally describe these species and discuss their morphological and ecological features within the framework of their molecular phylogeny. Here, we treat four new species of Cora plus an additional new species of Dictyonema, all found in the same area in the Orinoquia region in eastern Colombia. Cora casanarensis L. Vargas, Moncada & Lücking resembles C. reticulifera but differs in the branched lobes with incised sutures and with broad, shallow concentric ridges; it grows on rock instead of soil. Cora fimbriata L. Vargas, Moncada & Lücking can be distinguished from C. casanarensis in the olive color when fresh, the absence of distinct concentric ridges, and the marginal cilia. Cora setosa L. Vargas, Moncada & Lücking is a very distinctive taxon, with a similar ecology as C. aspera but with a smaragd-green color when fresh and with broad, concentric ridges; it is also unique by forming almost circular lobes. Cora undulata L. Vargas, Moncada & Lücking is morphologically close to C. ciferrii; it differs, however, in the smaller lobes with dark olive-green color when fresh and in the saxicolous growth. Finally, Dictyonema giganteum L. Vargas, Moncada & Lücking can be separated from D. sericeum s.str. by the large, thick lobes with broad white prothallus and with abundant, white surface setae. All new species of Cora fall into only one of the two major Cora clades and are not closely related to the morphologically most similar taxa.

Bulbothrix asiatica Y. Y. Zhang & Li S. Wang sp. nov. is proposed to accommodate specimens with a black lower surface, an emaculate and cracked upper surface and salazinic acid in the medulla. The species is currently known only from Cambodia and southwestern China. Other Parmeliaceae with bulbate cilia here newly reported from Cambodia are: Bulbothrix lyngei, B. subscortea, Relicina abstrusa and R. circumnodata. Phylogenetic trees for Bulbothrix are established to assess the affinities of the new species and test for a differentiation of saxicolous and epiphytic populations of B. subscortea. A key to these species is presented.

Dictyonema huaorani, a new species represented by a well-developed specimen found in the Ecuadorian Amazon region, is described in this paper. The material was collected during a Harvard ethnobotanical expedition in 1981 and originally determined by Mason E. Hale Jr. as belonging in the genus Dictyonema (D. sericeum s.lat.) and possibly representing an undescribed species. The species is morphologically distinctive in forming densely woven, semicircular thalli, closely resembling those of the paleotropical D. ligulatum but lacking clamps and with hyphal sheath around the photobiont filaments that resembles those of Cyphellostereum species. The species was reported to have hallucinogenic properties and chemical analyses suggest certain substances present that are shared with the hallucinogenic mushroom Psilocybe cubensis. Due to our inability to use pure reference compounds and scarce amount of sample for compound identification, however, our analyses were not able to determine conclusively the presence of hallucinogenic substances.

Our continuing investigation of lichen collections within Everglades National Park have revealed four new species to science, Cryptothecia fuscopunctata, Diorygma basinigrum, Herpothallon hyposticticum and Platygramme coccinea. In addition, the following 16 taxa are reported for the first time to the continent north of Mexico: Coenogonium isidiatum, C. isidiiferum, C. nepalense, C. subdilutum, Enterographa subserialis, Fellhanera rhapidophylli, Malmidea flavopustulosa, Melanotrema platystomum, Phyllopsora labriformis, Pyrenula dissimulans, P. minor, P. parvinuclea, P. pleiomera, Ramalina leptosperma, Sclerophyton seriale and the lichenicolous fungi Labrocarpon canariensis encountered on Ochrolechia africana. A brief discussion comparing richness and density of the corticolous Everglades lichen flora with that of Central and South America lowland tropical forests is presented.