UV spectroscopy confirmed that the lichen-derived pulvinic acid derivative epanorin forms complexes with metal ions (Cu² , Fe² , Fe³ , Mg² , Mn² , Zn² ) at two binding sites both under acidic and alkaline conditions. Similar observations in rhizocarpic acid suggest that the amino acid moieties in both epanorin and rhizocarpic acid are responsible for metal binding at low pH, whereas pulvinic acids without an amino acid moiety bind only to metal ions under alkaline conditions. Metal complexation at low pH is thought to enable lichens with epanorin or rhizocarpic acid to colonize acidic, nutrient-poor substrata, whereas lichens with pulvinic acids without an amino acid moiety prefer either neutral to alkaline or acidic but nutrient-rich substrata. High dissociation constants of epanorin (pK_a = 4.9) and rhizocarpic acid (pK_a = 4.5) in methanol suggest that the amino acid groups in these substances prevent them from acting as a protonophore. Otherwise the relatively high pK_a values of epanorin and rhizocarpic acid would result in damage of lichens containing these substances at low pH, which is not observed.

Patterns of diversity and distribution of bryophytes were surveyed across three different forest types: secondary montane forest and tree plantations of Cupressus lusitanica and of Pinus patula, in the Andean Central Cordillera of Colombia. A stratified sample design was employed to distribute 40 transects (50 × 40 m each) across forest types, each one conforming to a minimum of ten randomly selected plots of 1 m². One-Way ANOVA and rarefaction curves were employed to analyze species richness. Species richness was weighted by the total number of plots surveyed in each transect with a minimum of 10 plots with bryophytes present. Detrended Correspondence Analysis (DCA) was used to analyze the patterns of distribution of bryophyte species among forest types. Correlation analyses were employed to test the influence of environmental and spatial factors for species richness and distribution. A total of 151 species were recorded. Weighted species richness was higher in secondary montane forests and cypress plantations than in pine plantations. Bryophyte abundances differed among forest types, with the highest level recored for the cypress plantations. The DCA showed a high floristic similarity among forest types. Soil pH, slope and light availability were the principle factors explaining bryophyte distribution, which support habitat specialization as the main mechanism addressing species distribution within forest types. At a mesoscale level, however, a continuous dispersal of propagules among forest types was considered the main mechanism determining the regional pattern of bryophyte distribution.

Micro-morphological studies on mosses are not common, but have the potential to illuminate the nature of taxonomic characters. Data on the structure and development of leaf cell papillae in the Sematophyllaceae obtained using light and scanning electron microscopy techniques are presented to assess developmental similarity and congruence with taxonomy. Two morphological and developmentally distinct kinds of papillae were identified; 1) dome-shaped to conical, tapering to a firmly rounded apex (“conical”), and 2) a more flaccid, baggy form, that is often flat-topped and wider distally than proximally (“baggy”). Conical papillae first appear as slight protrusions that gradually increase in height, whereas baggy papillae progress through a series of developmental sizes and forms. Conical papillae occur in most papillose taxa, whereas baggy papillae are present only in Taxithelium subgenus Taxithelium.

Plagiochila microdictyon Mitt., previously considered a synonym of P. circinalis (Lehm. & Lindenb.) Lindenb., is a distinct species, with a limited distribution in northern New Zealand. This species has the coarse, nodular leaf cell trigones of P. circinalis, but has straight, non-coiled androecia, the male bracts toothed at the apex and united with the bract above. In dorsal aspect, the opposing leaf bases are separated by a conspicuous groove, leaving the surface of the stem narrowly exposed.

Lichen diversity and coverage on willow oaks were measured in 16 parks in the Raleigh area of North Carolina, plus one natural area in nearby Orange County (control), as a pilot study for a potential statewide lichen biomonitoring project. This study's objectives were to assess the air pollution effects of the Raleigh urban airshed on these lichen communities, and determine what methods are best for this bioassessment. Thirty-one macrolichens and 24 crustose lichens were detected with average trunk floras of 4–20 taxa per site. Lichen communities were dominated by: Buellia curtisii, Candelaria concolor, Candelariella reflexa, Lecanora strobilina, L. hybocarpa, Physcia millegrana, Pyxine subcinerea and Punctelia rudecta, of which the macrolichen species are known to be pollution-tolerant, including Py. subcinerea, which is here described as such. The control site largely lacked these species, and harbored lichens more representative of nearby protected forests. All sites lacked pollution-sensitive beard lichens (Usnea spp.) and cyanolichens that are found in protected forests. Lichen Diversity Value (LDV) analysis of macrolichens did not result in the expected pattern of increasing diversity further away from the city center, due to a number of factors. However, negative correlations were found between lichen diversity variables and human population and traffic variables, as well as between tree trunk size and crustose lichen diversity. Macrolichen species richness and abundance were higher on mossy trunks, but crustose lichen diversity was lower. Bark texture and moisture as well as air quality appeared to influence the structure and composition of these lichen communities. In summary, the lichen communities on the urban trees appeared to be affected by the region's air pollution both in terms of diversity and species composition. Diversity measures are best tracked if the total community is measured, not just the macrolichen component. Crustose lichen coverage should also be incorporated in abundance studies.

Xanthoparmelia teydea is described as new to science. This new species was found on basaltic rocks in the high mountains of the Canary Islands, in El Teide National Park (Tenerife Island). A description of the species is given together with notes on its chemistry, distribution, ecology and taxonomy. Possible associated taxa are briefly discussed.

Fifty white fir, red fir, incense cedar, Jeffrey pine and sugar pine were surveyed for corticolous bryophytes and macrolichens in the Teakettle Experimental Forest. Epiphyte abundances were estimated by percent cover in 5 m strata from ground-level to tree-tops. Gradients of bark pH within tree species and stand-level vapor pressure deficit (VPD) were also measured. Mosses had a strong positive association with white fir and proximity to perennial water. Clustering of trees in macrolichen space resulted in four significant groups: white fir, red fir, incense cedar, and Pinus. The lichens Ahtiana sphaerosporella and Letharia indicated the red fir group, Hypogymnia imshaugii and Melanelia elegantula the white fir group, and Nodobryoria oregana the Pinus group. Two nitrophilous lichens, Xanthoria polycarpa and Candelariella efflorescens were strongly positively associated with white fir, and absent from the Pinus species. Bark pH distinguished presence/absence of moss and composition of macrolichens among tree groups, while increasing VPD with height best explained within-group community structure. To foster epiphyte richness and diversity in this mixed-conifer forest, a heterogeneous mix of mature tree species should be retained when thinning, and mature trees in the narrowly confined riparian zone should not be harvested.

Two collections of a chemically distinctive corticolous Buellia species were discovered in the herbarium of Sampaio at the University of Porto (po). A detailed morphological and chemical study of the specimens, as well as of additional material for comparison purposes, showed that they agree with Buellia triseptata, only differing by containing xanthones. They are here provisionally regarded as representing a new chemotype of B. triseptata. Further, the generic assignment of B. triseptata is discussed.

Physconia grumosa, a species previously known from Asia, is reported from Alaska, the Rocky Mountains (Colorado, New Mexico), New England (Maine) and the Great Lakes region (Michigan, Minnesota, Wisconsin, Ontario). This species is similar to P. detersa, differing primarily by the type of propagules formed along the lobe margins: granular to weakly coralloid isidia and few to many dorsiventral lobules instead of true soredia. A description of the species is provided and comparisons with similar species are given.

In seed plants, the occurrence of spatial segregation of the sexes (SSS) along environmental gradients is well documented. SSS in bryophytes is usually more extreme than in seed plants, yet few bryophyte studies have explicitly linked SSS to environmental variables. For Marchantia inflexa, in which males are found beneath more tree-canopy openness than are females, we tested whether morphological, physiological and life history patterns are consistent with this sex-specific association to canopy openness. To accomplish this, we quantified morphology, physiology and life history differences between two light conditions for each sex. Responses to light levels were mostly analogous to sun and shade leaves of seed plants. However, we found that males had lower chlorophyll a∶b ratios (indicative of low-light plants) than females, contrary to our prediction.

This study provides the first report that Sphagnum centrale and S. henryense are allopolyploids. Microsatellites show S. henryense and S. palustre to be conspecific. In contrast, they show S. centrale to be genetically distinct from S. palustre s.l. In addition to differences in alleles and allele frequencies, the patterns of observed heterozygosity across 17 microsatellite markers also differed between S. centrale and S. palustre s.l. This represents a dimension of genetic differentiation that is not detected or addressed by statistical approaches such as AMOVA or Principal Coordinates Analysis. The patterns of microsatellites further provide preliminary evidence suggesting that S. centrale and S. palustre have one parental taxon in common and differ in the second.

A comparative study of the morphology, anatomy and chemistry of Buellia lindingeri and Rinodina hallii clearly shows that these taxa are very closely related but not conspecific. The unique epihymenia distinguishes them from most species of both Buellia and Rinodina but, as they are more closely related to Rinodina, Buellia lindingeri is transferred to that genus.

Recent reconstruction of the phylogenetic relationships of hornworts has revealed novel hypotheses of unique common ancestries. The genus Megaceros, for example, was shown to be polyphyletic with New World species nested within Nothoceros. Here we present a sampling of most widely recognized species of both genera to provide a phylogenetic delimitation of Nothoceros and Megaceros based on the genes rbcL and nad5. The unique ancestry shared by Nothoceros and the New World species of Megaceros is confirmed. This clade, except for the New Zealand endemic N. giganteus is restricted to the American continent. The genus Megaceros is redefined to comprise only Asian and Australasian species. The three widely accepted American species of Megaceros, M. aenigmaticus, M. fuegiensis and M. vincentianus are transferred here to Nothoceros. The lack of defining morphological characters for Nothoceros along with its morphological diversity highlights the need for further taxonomic, morphological and ultrastructural studies of the genus.

This study provides the first report that Sphagnum mendocinum (Sphagnum section Cuspidata) and S. papillosum (Sphagnum section Sphagnum) are allopolyploids. Sphagnum mendocinum is an intersectional allopolyploid, with parental species from Sphagnum sections Cuspidata and Subsecunda. It is the third intersectional alloploid species reported for Sphagnum. The gametophytically allodiploid cytotype of S. papillosum was detected in Europe, North America, and Japan. It appears to be the predominant, if not the only, cytotype for this species. Our results may warrant re-examination of the report of a haploid (n  =  x) cytotype for S. papillosum.

Hypogymnia magnifica X.L.Wei & McCune is described as a new species of lichenized fungi from high elevations in Yunnan and Sichuan Provinces in southwestern China. Previously lumped under H. taiwanalpina, H. magnifica is readily distinguished from that species by its large size (commonly to 30 cm or more diam.), broad, rather appressed lobes that are contiguous to subcontiguous, sparse perforations in the upper and lateral surfaces, whitish color in the field (when dry), and lacking 3-hydroxyphysodic acid. Hypogymnia magnifica and H. taiwanalpina appear to be allopatric, with the former restricted to southwestern China and the latter restricted to far-east Asia (Taiwan and Japan).

Specimens of Caloplaca belonging to the group of C. citrina (Hoffm.) Th. Fr. were collected in different localities in the provinces of Buenos Aires (Argentina) and studied using morphology and nrITS data. They were identified as C. austrocitrina Vondrák, Riha, Arup & Søchting, a species newly described from the Black Sea area, but also found in other European countries. These findings are the first mention of this species for South America and broaden its distribution range considerably. The results also show that the specimens from Argentina are genetically very similar to the European ones and that the variation in this gene within the species seems to be very low.

Fissidens minutifrons is described and illustrated from Ecuador. The species belongs to subgenus Pachyfissidens section Pachyfissidens and is similar to F. grandifrons and F. geijskesii. The distinctive features of the species include: closely imbricate, narrowly lanceolate, elimbate leaves; taxifolius type costae; smooth laminal cells that vary from 2–4-stratose near the costae to 1–2-stratose at the margins in dorsal and ventral laminae, and 1–2-stratose from costae to margins in the vaginant laminae; laminal cells differing greatly in size, decreasing in size from costae to margins, juxtacostal cells and several inner rows larger and quadrate to oblong, several rows of outer (marginal) cells smaller and quadrate to hexagonal, the areas of larger inner cells and smaller outer cells greatest in the vaginant laminae.

Rhodobryum (Schimp.) Limpr. is studied for Argentina, based on herbarium specimens and on specimens collected during field expeditions from 2005 to 2008. Two species are recognized for the Argentinian bryological flora. Rhodobryum beyrichianum (Hornsch.) Müll. Hal. is widely distributed in the mountainous areas of northern Argentina and is a new record for the provinces of Corrientes, Tucumán and Salta. Rhodobryum subverticillatum Broth. is reported for the first time for Argentina; it occurs in Jujuy and Salta provinces. Rhodobryum roseolum (Müll. Hal.) Paris, known from a single Argentinian specimen, is excluded from the flora and synonymized with R. beyrichianum. Rhodobryum aubertii (Schwägr.) Brid. and R. roseum (Hedw.) Limpr. are excluded from the bryoflora of Argentina. The status of R. platense (Müll. Hal.) Paris remains obscure; it possibly is not a species of Rhodobryum. Key, descriptions, illustrations, SEM photographs and distribution maps are provided, and habitat ecology and the distribution in Argentina and total distribution are given. Rhodobryum ontariense (Kindb.) Kindb. is recorded first time for Bolivia and Peru. Rhodobryum dentatum (Ochi) T. J. Kop. & Fuertes is a new combination and lectotype is selected for Bryum hieronymi Müll. Hal.

Herpothallon rubroechinatum is described from the U.S.A. (Florida), Costa Rica and Peru. The new species is characterised by scattered red anthraquinone crystals being attached to hyphae projecting from the thallus, the globose to cylindrical pseudoisidia, a closely adnate thallus, and psoromic acid as the main lichen compound; pycnidia are common at the tips of the pseudoisidia. The medulla of the new species shows a patchily distributed amyloid reaction. Contrary to previous reports, the amyloidity of the medulla was observed in all Herpothallon species re-investigated during this study. H. rubroechinatum is compared to the two other red pigmented species that contain psoromic acid, H. australasicum that lacks pigment crystals on the pseudoisidia, and H. globosum that has a loosely attached thallus and a well developed red hypothallus.

Cyanolophocolea echinella R.M.Schust. is an intriguing species, possessing some character states characteristic of the genus Chiloscyphus, such as the ability to produce both male and female gametangia on leading shoots, while having other features that are generic characters of Heteroscyphus, namely presence of gametangia on short, abbreviated lateral-intercalary branches. Its systematic identity was here studied using morphological and DNA sequence data of the chloroplast gene regions of rbcL, rps4 and trnL-F. Thirty-seven exemplars including eight of Cyanolophocolea echinella, 27 of Lophocoleaceae and two of Plagiochilaceae were used for phylogenetic reconstruction using both maximum parsimony and Bayesian inference methods. Our analyses placed Cyanolophocolea echinella within Heteroscyphus with strong support. Heteroscyphus echinellus (Lindenb. & Gottsche) J.J.Engel & XiaoL.He is proposed and based on morphological variations two varieties, var. echinellus and var. hyalinus J.J.Engel, are recognized. A large indel (59 base pairs) and one substitution in the trnL intron region, and also one substitution in the intergenic spacer region were found in the trnL-F in two Cyanolophocolea echinella exemplars both with hyaline oil-bodies. This indicates rapid molecular evolution might have occurred within the species.

Phylogenetic relationships of 36 samples of Mannia and other Aytoniaceae were inferred based on sequences of the chloroplast trnL-trnF region and partial nuclear ribosomal LSU (or 26S) gene and using Targionia hypophylla and Athalamia hyalina as outgroups. Maximum parsimony, maximum likelihood and Bayesian analyses were conducted on individual and combined molecular datasets. All phylogenetic tree topologies showed polytomies but suggest that Mannia has evolved from within Asterella and that there are two supported Mannia clades. Because Mannia is paraphyletic, with A. gracilis most closely related to M. triandra and M. pilosa, A. gracilis is transferred to Mannia. The major morphological differences between those genera are reevaluated. Based on molecular and morphological evidence Mannia is divided into the subgenera Mannia and Neesiella; Asterella subg. Graciles becomes a synonym of Mannia subg. Neesiella.