A morphological family concept for Trichocoleaceae Nakai is fully elucidated, and three genera, Eotrichocolea R.M.Schust., Leiomitra Lindb.and Trichocolea Dumort., are recognized. In the genus Leiomitra three species, L. breviseta (Steph.) R.M.Schust., L. capillata Lindb., and a new combination L. merrillana (Steph.) T.Katag., are recognized for Southeast Asia including the New Guinea Islands. Two new synonyms are proposed for L. merrillana: Jungermannia tomentella var. subsimplex Nees, and Trichocolea obconica Steph.

A monograph and the first phylogenetic study of the moss genus Hymenodon (Orthodontiaceae: Bryophyta) is presented based on morphological and molecular data. Evolutionary patterns are evaluated using phylogenetic analyses that incorporate newly acquired and assembled morphological (30 characters) and molecular sequence (rps4 gene and partial rps4-trnS intergenic non-coding spacer) data. Parsimony and maximum likelihood methods were applied for phylogenetic analyses using Leptotheca boliviana, L. gaudichaudii, Orthodontium lineare, and Orthodontopsis bardunovii as outgroups. The genus Hymenodon and sect. Hymenodon were both found to be monophyletic, whereas Hymenodon sect. Polystichella was found to be paraphyletic; thus, the sections are not upheld in this new classification. Hymenodon chenianus was nested within the H. pilifer subspecies. As Hymenodon chenianus is morphologically unique, and there are several characters that can distinguish each subspecies of H. pilifer, H. pilifer subsp. sericeus and H. pilifer subsp. tenellus are reclassified at the species level, as H. sericeus and H. tenellus, making a total of eight accepted Hymenodon species. Six species occur in Australasia (Malesia, southeastern Australia, Tasmania, New Zealand, and New Caledonia), while two species are found only in the Neotropics (one in continental Latin America and one in the Caribbean). The known range of Hymenodon aeruginosus is extended into Panama, Colombia, and Paraguay. Taxonomic history, synonymy, species descriptions, distribution, habitat information, and a dichotomous key to the species are provided.

The formerly monotypic genus Eotrichocolea is enlarged to accommodate E. furukii, a new species from Southeast Asia. Eotrichocolea furukii is characterized by incubous leaf insertion, robust stem without paraphyllia, well-developed stem cortex, heavily thickened walls at the distal ends of terminal cells of cilia, and absence of Acromastigum-type branching.

The taxonomic status of two poorly known Andean species is reviewed. Their diagnostic characters are illustrated and discussed. Bartramia microbasis Müll. Hal. is proposed as a new synonym of Anacolia laevisphaera (Taylor) Flowers and Mielichhoferia modesta Müll. Hal. is reduced to synonymy of Pohlia wahlenbergii (F. Weber & D. Mohr) A. L. Andrews. Four new lectotypes are selected, including for Glyphocarpa laevisphaera Taylor and Bartramia subsessilis Taylor.

By most accounts, Plagiomnium cuspidatum is a typical bisexual, diploid species with n  =  12 throughout its wide range. Beginning with Lowry's (1948) chromosome count of n  =  6 for a collection from northern Florida, however, there have been sporadic reports of haploid or unisexual plants of this species. Unfortunately, none of these cases has been examined closely enough for sexuality, ploidy level, and possible morphological or other differences to be firmly established. Our studies of natural populations from Florida and Georgia reveal that there is a previously undescribed species that differs from P. cuspidatum in sexual condition, ploidy level, morphology, and ecology. This unisexual species has a chromosome number of n  =  6, elliptic leaves with teeth that extend more than halfway down the margin, leaf cells mostly < 25 µm, and a preference for circumneutral soils associated with limestone. Its closest relatives in sect. Plagiomnium are P. cuspidatum and P. acutum, but Nei's (1978) unbiased genetic identities of 0.669 and 0.705, respectively, show that it is strongly differentiated from both (Wyatt & Odrzykoski 1998). Independent evidence of the distinctiveness of these populations from the southeastern United States comes from phylogenetic reconstructions based on sequencing of chloroplast (rps4, rpL16) and nuclear (ITS2) gene regions by Harris (2008).

Within the Lejeuneaceae the lobule papilla has been conceived to occupy three positions: proximal, distal, or ental of the apical tooth. This concept rests on the presupposition that the apical tooth in all species is homologous, an assumption that has been questioned but not demonstrably falsified. This paper describes a situation where characters describing the position of marginal papillae fail the test of conjunction, an explicitly testable criterion of homology, by co-occurring within an individual. This situation is presented by Cheilolejeunea oscilla, a new species from Queensland Australia. Variation in lobule morphology within individuals of C. oscilla demonstrates that a change from proximal to distal lobule papilla is achieved without altering the topological relationships between the first and second lobule teeth, and the lobule papilla. Therefore, the marginal papilla occupies the same position, proximal of the first lobule tooth, in all species of Lejeuneaceae subf. Lejeuneoideae, and apical teeth within typical Cheilolejeunea and Lejeunea are not homologous. The apparent difference in papilla position is due to the second lobule tooth being elaborated, and the first lobule tooth being incorporated into the lobule margin in typical Cheilolejeunea. One defining morphological character of Cheilolejeunea may be the presence of an elaborated second tooth, and on this basis the new combination Cheilolejeunea norrisii is proposed for a Tasmanian species previously referred to Lejeunea. The views of Mizutani and He, that referring to ‘apical’ teeth is ambiguous and the terminology ‘distal’ or ‘proximal’ when applied to lobule papilla position is positively misleading, are upheld. The need for descriptions of characters to accurately encapsulate the homology hypotheses they represent is stressed, and the need for greater attention to homology assessment when liverwort taxonomists propose characters and character states to describe their plants is again reiterated.

Parmelina quercina is a well-studied foliose macro-lichen found on rocks and trees in the Northern Hemisphere. Recent studies support multiple species within P. quercina based on material from Europe, North America and western Asia. The identities of Parmelina quercina s.lat. reported from eastern Asia and Alaska remain unknown. We compared DNA sequences, secondary chemistry and morphological traits of Parmelina from Alaska, Russia and China. These data support the resurrection of Parmelina yalungana to accommodate eastern Asian and Alaskan material. Parmelina yalungana differs from congeners in ascospore dimensions, geographic range and molecular data from three gene loci. We place P. yalungana in the phylogenetic context of the P. quercina group using DNA from Alaskan and Russian material.

This study provides a molecular phylogeny of Solenostoma and Plectocolea based on trnL-F and trnG-intron cpDNA sequences of 25 species represented by multiple accessions from different regions of Russia and some adjacent countries. Phylogenetic trees constructed using maximum parsimony, maximum likelihood and Bayesian methods are mostly congruent, except for an unstable position of P. vulcanicola, P. rosulans and S. caucasica. Based on our analyses we accept narrow generic concepts and provisionally conclude that only P. hyalina and the P. obovata-P. subelliptica-P. obscura-P. harana-P. emarginata complex should be transferred to the genus Solenostoma. Moreover, two species new to science are described and three varieties are elevated to the species level. Morphologically, Solenostoma rossica Bakalin et Vilnet is characterized by heteroicous inflorescences, red-purple pigmentation restricted to the perianth beak and a whitish-colored stem. Solenostoma major (S. Hatt.) Bakalin et Vilnet is characterized by deep purple rhizoid coloration and wide, flattened, undulate and distant leaves. Solenostoma ochotensis Bakalin et Vilnet has a Solenostoma-like perianth and well-developed plectocoleoid perigynium. Plectocolea kurilensis (Bakalin) Bakalin et Vilnet is similar to P. infusca s. str. but differs by commonly having smaller, grayish and more numerous oil-bodies, deflexed antical leaf margins, undulate leaves and purplish to almost purple rhizoids. Plectocolea ovalifolia (Amak.) Bakalin et Vilnet is only distantly similar to P. infusca s. str., as it has purple rhizoids, oil bodies unlike P. infusca, a smaller plant size, generally distant to rarely contiguous leaves, and ovate leaves, as opposed to lingulate to broadly or transversely elliptic leaves. It is suggested the new species originated in the contact zone of circumboreal and temperate East Asian floras with the possible influence of modern volcanic activity.

Two new Ulota species with multicellular spores, Ulota billbuckii and U. streptodon, are described from southern Chile. The new species are usually found growing together and sometimes forming mixed cushions or mats on different trees, with a preference for Nothofagus betuloides and N. antarctica. The new Ulotae are easily differentiated from each other as well as from other Ulota species with multicellular spores by a set of sporophytic traits including two very uncommon peristome configurations. In this paper, both species are described, and the differences between them as well as from other Ulotae with similar endosporic germination, and from superficially similar species, is discussed.

Many of the species living on our planet remain undiscovered, among these over one million Fungi. One approach to account for undescribed species is the search in unusual habitats. Here we report on the unexpected finding of a new species of Lepidostroma (Atheliales: Lepidostromataceae) from the semi-arid Caatinga biome in northeastern Brazil. It is only the fifth species of this enigmatic genus and only the third from the Neotropics, and the fourth species to be described within the past four years. DNA was extracted and the ITS and nuLSU partitions of the nuclear rDNA were sequenced. A phylogenetic tree was computed under a maximum likelihood framework using an alignment of selected Basidiomycota (Atheliales, Agaricales, Boletales, Russulales, Cantharellales). The new species differs from other species in the genus by the crustose rather than squamulose thallus. Molecular sequence data place the species as unsupported sister to Lepidostroma akagerae. The crustose thallus resembles that of Multiclavula species, which are phylogenetically unrelated. This study underlines that novel lichenized Fungi can be discovered in unusual habitats. The Caatinga vegetation is to a large extent threatened by habitat destruction and the discovery of such an unusual species underlines the importance of this unique biome for conserving diversity in tropical South America. Systematically, the new species is relevant because it represents the only species of Lepidostroma with a crustose, Multiclavula-like thallus, presenting a striking example of parallel evolution in lichenized Basidiomycota.