River banks are home to unusual, morphologically highly specialized bryophyte taxa, which have been little studied. Here we describe a novel rheophilous and epiphyllous liverwort from Ecuador, Cololejeunea stotleriana, with many unusual morphological features such as robust stem, flat, triangular lobules, large rhizoids fields that are not produced near the base of each leaf, superfertility and clustered gynoecia. Because of its puzzling morphology, we used two regions of the chloroplast genome (trnK-H, trnL-F) to explore the systematic affinity of this new species. It turned out to be the second member of the subgenus Chlorolejeunea and the first record of this Asiatic subgenus from the New World. The species was found growing associated with the rare mosses Fissidens hydropogon and Lepidopilum caviusculum, both only known from their type specimens collected 150 years ago. The unusual morphological traits of Cololejeunea stotleriana are interpreted as adaptations to the harsh rheophilous and epiphyllous environment. The deviating morphology of the new species indicates that extreme morphological transformations can obscure the phylogenetic signal present in morphological data.

Lamellocolea was previously a monotypic genus endemic to New Zealand. Lamellocolea integrostia, a second species in the genus, is described and illustrated from New Zealand.

We investigated the locomotory apparatus of the mid-stage spermatid of Aneura pinguis in order to gain a better understanding of the evolution and development of gamete ultrastructure in liverworts. The locomotory apparatus consists of two staggered but overlapping basal bodies and a multilayered structure made up of a spline and lamellar strip. The basal bodies include a transition region between the basal body and flagellum containing a short stellate pattern and dense matrix. The spline's maximum width is 20 microtubules and reduces in number at the posterior of the multilayered structure; however, this number appears variable at the mid-stage of development and so it is recommended that the mature spermatozoid be investigated for this feature. The anterior basal body is situated over the spline aperture, which measures 2 microtubules in width and 0.85 µm in length. The lamellar strip measures 4.06 µm in length and 0.60 µm in width, and is spatulate in shape with a right lateral offset or keel. When compared with Riccardia multifida, the two locomotory apparatuses share an overall similarity of features, such as a closed spline aperture, similar lamellar strip shapes, and similar stellate pattern lengths. However, A. pinguis has several distinctive features, such a wider spline and a longer posterior basal body that may be adaptations associated with a rapid increase in DNA from a polyploidization event. These results are fully consistent with an 85 year old light microscope study where illustrations depict a similar posterior flagellum distance from the front of the cell. Observations of male gametes of liverworts are imperative to illuminating details of character evolution within this lineage and could provide a model for further understanding of evolutionary modifications in the development of complex cells.

When originally described from deeply shaded banks in Malaysia and Borneo the thalloid liverwort Mizutania riccardioides was tentatively assigned to a new family in the Metzgeriales. However, phylogenetic inferences from sequence data indicate that it arose within the Calypogeiaceae. The present ultrastructural study of Mizutania reveals that a unique tripartite wall structure underlies the verrucose surface of the thalli. Outside an inner fibrillar layer, like that in other bryophytes, its middle stratum comprises closely packed lamellae. This recalls similar wall structures in blue iridescent pteridophytes and is most likely responsible for the same phenomenon. Unlike the rounded papillae contiguous with the outer wall layer in other liverworts, the outer part of the wall in Mizutania comprises irregular blocks of dense material, many of which become detached but remain embedded in a thick investiture of mucilage. These dense blocks contain high concentrations of aluminum and silicon; this is the first time that both these elements have been found co-localized in bryophytes. Mizutania has swollen, fungus-containing rhizoids similar to those of the Lepidoziaceae, Cephaloziaceae and Calypogeiaceae but unlike the last family, its gemmae are endogenous rather than exogenous. Whilst the fungal association is in line with the affinities determined from sequencing, its endogenous gemmae, unique wall structure and apical organization are robust morphological criteria for retaining a subfamial rank within the Calypogeiaceae.

Frullania is a large and taxonomically complex genus. Historically, Amphijubula, Neohattoria, Schusterella, and Steerea have either been recognized as distinct segregate genera, or, subgenera within Frullania. In contemporary Frullania systematics, Amphijubula has been classified at the subgenus level. Because of its aberrant morphology and nested position within F. subg. Microfrullania based on a prior molecular investigation of the genus, we lower this subgenus to a section as F. subg. Microfrullania sect. Amphijubula. Three taxa, including a new species from New Zealand described here, are currently ascribed to F. sect. Amphijubula. Detailed descriptions and photographs are provided for F. lobulata, F. microcaulis, and F. truncatistyla, as well as a determination key. The distinguishing features of F. sect. Amphijubula include the leaf lobes with acute or acuminate to apiculate apices and the distinctive lobule with a conspicuous projecting, angular cell, inserted directly above the lateral slit. Secondary character-sets that aid as supplementary sources of data for differentiation include the small plant size, and characters associated with the female bract, seta anatomy and elater number.

The first ever liverwort and hornwort checklist is provided for Jamaica. We report 332 taxa in 314 species, 14 of which are invalid, illegitimate or in orphaned genera but we do not know where to place them. An additional 16 of the reported taxa are rejected as erroneously reported from Jamaica. The list is based on over 270 literature references, including monographs, regional studies, and molecular investigations. Except for a few early works in the 18^th and early 19^th century, and a scattering of other studies, the liverwort and hornwort flora of Jamaica has received negligible attention, despite its apparent diversity. The knowledge of the liverwort and hornwort flora, both in Jamaica and regionally in the Caribbean, remains so poor it is too early to reliably comment about range-restricted or endemic species. We predict that a number of new records remain to be reported, based on regionally widespread species that have been recorded elsewhere. On the other hand, it is envisaged that a number of the taxa presented here maybe synonyms of other taxa as they are taxonomically insufficiently known. As a consequence, Anastrophyllum harrisanum Steph. is reduced to a new synonym of A. tubulosum (Nees) Grolle.

Three species have been formerly segregated from Metzgeria in the genus Apometzgeria. One of the species, A. frontipilis, is endemic to South America but the second, A. pubescens, is currently understood as having a bipolar range with populations across the Holarctic and in southern South America. The third species, A. longifrondis, was described from China (and is not included in this study). Species of bryophytes that range across continents and have little or no morphological variation among populations may nevertheless harbor morphologically cryptic genetic lineages. We used nuclear and plastid sequence data to examine the phylogenetic relationship between Apometzgeria and Metzgeria, and phylogeographic patterns in taxa assigned to Apometzgeria. Two species often assigned to Apometzgeria are phylogenetically embedded within Metzgeria in two separate clades, one comprising all Holarctic A. pubescens and a second with A. pubescens from South America and all accessions of A. frontipilis. Phylogenetic and haplotype analyses reveal a lack of phylogeographic structure among A. pubescens plants from throughout its Holarctic distribution. However, A. pubescens in South America is more closely related to A. frontipilis and species of Metzgeria from South America than to any A. pubescens from the Northern Hemisphere. Thus, A. pubescens is Holarctic in distribution and morphologically similar plants form a divergent lineage in South America. Our results do not support Apometzgeria as a separate genus in the Metzgeriaceae.

Contemporary taxonomists usually recognize a single species in Dumortiera, which is widely distributed through tropical and subtropical regions and extends into some temperate regions. Two subspecies, D. hirsuta subsp hirsuta and subsp. nepalensis, may be recognized, and both of these were thought to occur in Central America. We sequenced four loci, the nuclear internal transcribed spacer region ITS, and three chloroplast loci (rbcL, psbA-trnH and rpoC1) from 50 samples of Dumortiera across its geographic range to test for phylogenetic structure within the species and its congruence to morphological and geographic patterns. We also used light and scanning electron microscopy to examine morphological differences between accessions from Central America. Phylogenetic inferences reveal two highly distinct lineages: the first apparently restricted to Central America, and the second distributed across all the geographic regions sampled. This widespread lineage could itself be subdivided into several genetically and geographically distinct clades. The restricted Central American lineage contains plants that have a light green velvety appearance, due to an abundance of papillae on their upper thallus surface. These can therefore be distinguished morphologically from sympatric accessions of the widespread lineage, which are dark green, with a wide range of papillae densities (absent, few or abundant) on the thallus and usually with abundant marginal hairs. However, the wider application of these characters to lineages outside the Central American region has not yet been confirmed. We conclude that Dumortiera contains at least two, if not more, distinct species. The Asian epithet nepalensis does not seem applicable to plants in Central America, as the papillate morphotypes to which this name has been applied form an exclusively new world lineage. A thorough morphological revision of the genus, and reinvestigation of type material, is required.

Thalloid liverworts with a complex anatomy and with star-shaped epidermal pores with strongly thickened radial walls in the surrounding cells have traditionally been accommodated within the Cleveaceae, which comprises three genera: Athalamia, Peltolepis and Sauteria. Based on phylogenetic inferences from three chloroplast genes (psbA, rpoC1 and rps4) sampled for 41 accessions, we tested the circumscription and the relationships of these genera, using six species of the Aytoniaceae as outgroups. Four main lineages are resolved, two corresponding to Peltolepis and Sauteria and two composing a polyphyletic Athalamia. The latter is here divided into Clevea and a narrowly defined Athalamia. The traditional definition of genera of Cleveaceae based on two characters (carpocephalum stalk position and anatomy) is rejected and morphological characters defining the genera are re-assessed. A revised generic delimitation is presented, including a key to the genera. Evolution of the genera of Cleveaceae is re-evaluated in the light of molecular results, and the misleading influence of homoplasy on past morphological classifications and phylogenies is discussed.

Members of the liverwort family Fossombroniaceae are typically identified by the distinct ornamentation patterns on their spores. We have tested the hypothesis for Australian Fossombronia that using spore morphology is sufficient to identify species based on a monophyly criterion applied to a molecular phylogeny. We used the chloroplast markers rps4 and trnL-F and the nuclear internal transcribed spacer (ITS) region to develop a phylogeny based on multiple accessions per putative morphospecies. Whilst the relationship between species had little support, the results did strongly support seven out of the eight species groupings based on spore morphology.

The Madeiran laurel forest (Laurisilva) is a subtropical forest with a very rich bryophyte flora and is considered as one of the most important remnants of the evergreen laurel forest from the Tertiary period. The effect of the laurel forest tree species on the epiphytic bryophyte species richness and composition in Madeira Island was studied in 40 sites. A total of 160 trees, belonging to 19 different tree species were assessed in the laurel forest. For subsequent analyses, we focused on seven tree species, for which at least nine individuals were sampled. A total of 137 trees from 40 sites were thus available for statistical analyses. We recorded 110 epiphytic bryophyte taxa (59 species and one variety of mosses and 50 liverworts). Accumulation curves showed clear differences in bryophyte species richness between the different tree species, with typical laurel forest tree species harboring more bryophytes. Tree species also had highly significant effects on species density (mean species richness per 10 × 20 cm plot), with densities higher on the typical laurel forest trees. This was especially true for the liverworts and the endemics for which Clethra arborea, Laurus novocanariensis, Ocotea foetens and Persea indica exhibited higher species density than the two Erica species and Myrica faya. For mosses species density of the tree species tended to be more similar, only O. foetens showed a higher density and M. faya a lower. Endemic bryophytes were lacking on Erica species and almost lacking on M. faya. Concerning species composition, we found significant effects of the tree species sampled. There was a rather clear gradient from the two Erica species to the typical laurel forest tree species such as L. novocanariensis, O. foetens, and P. indica. An analysis of indicator species revealed ten significant indicator species for the typical laurel forest trees, C. arborea, L. novocanariensis, O. foetens and P. indica. Our results reinforced the importance of the laurel forest of Madeira as a hotspot of epiphytic bryophyte diversity whose species distribution is strongly shaped by the nature of the tree species.

Cloud forests are one of the most diverse and yet one of the most endangered ecosystems in the tropics. Epiphytic bryophytes are extremely diverse and abundant in this ecosystem where the palms are a dominant element. Slash and burn agriculture techniques usually do not cut the palms and they remain as isolated individuals in the middle of artificial grasslands or agricultural fields. Forest clearing creates new environments on the isolated trees that have been considered a refugee for “rare” canopy species, and the relationship of these “isolated” communities with forest communities has been considered to be distant. We sampled 99 plots on 11 individuals of the palm Dictyocaryum lamarckianum for a total effective sampling area of 15.9 m². The epiphytic communities comprised 72 liverworts and 21 mosses. Diplasiolejeunea alata and D. cavifolia are hereby reported for the first time from Colombia. We analyzed the changes in bryophyte diversity patterns between forests and man-made grasslands and how these patterns are related to the distribution of locally rare species. Our results showed a decrease in the number of species from the bottom to the top of the palm and from the forest to the grassland. Rare species were mostly concentrated in the forest independently of height. Common species moved on average 4 m downward on the palms in the grassland relative to the height on the forest. Ordination of the plots using NMDS provided evidence that the change in species composition is gradual between forests and grasslands and from the base of the palms to the canopy. We propose that the new communities generated by slash and burning practices are a combination of drought tolerant species from the forest and species that are commonly found in disturbed sites. In conclusion, isolated palms are not islands where canopy species can be preserved as they harbor only common species.

The Pyxine pungens complex comprises species producing atranorin in the upper cortex, lacking vegetative propagules and reacting K blackish purple in the pigmented medulla. Based mainly on the development of apothecia, pigmentation and development of the internal stipe and chemistry, three new species morphologically similar to P. pungens are described. Pyxine rhodesiaca and P. schechingeri are also treated and compared to this complex of species.

A short revision of the vagrant Aspicilia species of North America is presented based on morphological, molecular and ecological data. Vagrant Aspicilia are common lichens throughout the steppes of the western United States and in southwestern parts of Canada. Species delimitation of these lichens is difficult because of the paucity of morphological characters and large degree of variation. Inferences from nuITSrDNA sequences reveals that the North American specimens of A. fruticulosa are not most closely related to their Eurasian populations but instead share a unique ancestor with A. hispida. The specimens of A. fruticulosa from the New World are hereby recognized as a distinct species, A. rogeri. Its differentiation from the similar A. fruticulosa and A. hispida is discussed. The exclusion of A. fruticulosa from the N. American checklist is proposed temporarily.

Hattorioceros (J. Haseg.) J. Haseg. is a monospecific genus of hornworts with a single species, H. striatisporus (J. Haseg.) J. Haseg., previously known only from the Western Himalayas and Fiji. Here we report this genus as a new addition for China from Xizang (Tibet). Some previously unknown morphological characters, such as the presence of a single chloroplast with a pyrenoid per cell and the number of antheridia per chamber are added to the generic description.

A new rheophytic moss genus and species Yunnanobryon rhyacophilum occurring in fast-flowing rivers of western Yunnan and southern Guizhou Province is described and illustrated. It is a slender moss with stoloniform primary stems and intricately much branched secondary stems, flagellate-attenuate at the tips; small, ovate to ovate-lanceolate leaves with almost uniform areolation throughout the lamina of small, rounded, hexagonal to quadrate-hexagonal cells; coarsely serrate leaf margins in the distal portion; subpercurrent single costae; and very short, bicellular axillary hairs consisting of a large globular apical cell and a short, quadrate and brownish-tinged basal cell. The peculiar shape of the axillary hairs suggests a close alliance of this new genus with the Regmatodontaceae.

Extant models of long-term ecosystem nutrient status, largely formulated using data from mid- and low-latitude settings dominated by vascular vegetation, predict nitrogen (N) limitation in the early stages of primary succession and phosphorus (P) limitation in the latter stages. The aims of this study were a) to examine the use of mosses to establish ecosystem nutrient status; b) to test an existing model of nutrient limitation during long-term primary succession and c) to assess the connection between nutrient dynamics and the emergence of spatially structured vegetation in a high-latitude, moss-dominated community. Spatiotemporal changes in nutrient availability were inferred using tissue nutrient concentrations in a moss sampled from a long (850-year) chronosequence of lava flows in Iceland. This is the first use of bryophyte nutrient concentrations, even though they should be a good indicator of nutrient status in high-latitude habitats. Samples of the moss, Racomitrium lanuginosum, from different topographic positions were collected from seven lava flows of different ages (26–848 years) and analyzed to establish concentrations of N, P and major mineral nutrients. Concentrations of N were low on all sites and evidence of progressive N accumulation is lacking; increasing concentrations of phosphorus indicated increasing N limitation with terrain age. This pattern contrasts with other studies of long-term nutrient limitation, where N limitation reduces and P limitation increases with increasing terrain age. Concentrations of mineral nutrients did not vary significantly with terrain age. Nutrient concentrations were only weakly related to spatial patterning in the vegetation. It is likely that element concentrations were strongly influenced by inputs of allochthonous sediment. These findings suggest that mat-forming, pleurocarpous mosses may be used to infer long-term changes in N & P limitation during primary succession and that existing models of nutrient limitation may not be robust over century – millennial timescales in low productivity, high-latitude habitats.

The new lichen species Syncesia indica is described from southern India and is characterized by stromatoid ascomata, 3-septate small ascospores, and presence of protocetraric acid and traces of roccellic acid. The new taxon grows on tree trunk in evergreen forest in Shradighat regions of Karnataka. A key of all species included in the genus is provided.

We studied lichen photobiont diversity patterns of three epiphytic Nephroma species in a 900-ha boreal forest landscape using cyanobacterial tRNA^Leu (UAA) intron sequences. Our aim was to investigate if there was a link between lichen species identity, reproductive strategy, and photobiont selectivity. We show high photobiont specificity and selectivity within the forest landscape: only five closely related tRNA^Leu (UAA) intron genotypes were found from 232 Nephroma thalli. Two Nostoc genotypes were shared by N. bellum and N. resupinatum, while N. parile associated with two different genotypes. One genotype was only found from some specimens of N. resupinatum. On a single tree trunk all thalli of an individual lichen species usually housed the same photobiont strain, and the lichen species that mainly dispersed with fungal diaspores (N. bellum and N. resupinatum) usually shared identical photobionts. Both patterns were attributed to a founder effect presumably caused by relatively low colonization rates between trees. The photobiont spectrum of the symbiotically dispersing N. parile indicates that it maintained its own cyanobacterial symbionts. Our study shows that mycobionts of the diverse Nephroma guild do not exchange their cyanobacterial photobionts at random, and that reproductive strategy is reflected in species photobiont choice.

Erioderma mollissimum is a rare cyanolichen found on the foggy Atlantic coast of Canada. The rarity of E. mollissimum and the potential threat from human impact has led to conservation concern for this species in Canada. Recent finds on the island of Newfoundland suggest that the distribution of E. mollissimum may be wider than historically known. In order to better understand the environmental factors affecting distribution and to direct future search efforts a Mahalanobis predictive distribution model using a geographical information system (GIS) was developed for Atlantic Canada. The model suggests that only a small part of this region is suitable for E. mollissimum. This study provides an example of an alternative modeling technique to the traditional statistical methods for predicting lichen distribution.

Plagiothecium bicolor Warnst., known only from the holotype specimen collected by E. Ule on Mount Roraima, Brazil, is a synonym of Lepidopilum scabrisetum (Schwägr.) Steere.