Calymperaceae is a large moss family well represented in lowland tropical rain forests worldwide. To date, both infra- and extra-familial relationships in Calymperaceae remain largely unresolved. Here, we present a multi-locus phylogenetic hypothesis based on one ribosomal, one mitochondrial and four plastid markers from 61 taxa with the aim to: 1) test the monophyly of Calymperes; 2) evaluate the subgeneric classification for Syrrhopodon; 3) estimate divergence times in light of the “shadow of the angiosperms” hypothesis; and 4) examine the global-scale phylogeographic patterns in light of predictions that lowland tropical bryophytes have higher dispersal capacities than extra-tropical taxa. Our analysis, which now includes 15% of the family's Neotropical representatives, corroborates the monophyly of Calymperes, Mitthyridium and the Leucobryoid taxa, and demonstrates that leaf morphology (including leucobryoid characters) are evolutionarily labile traits. The large genus Syrrhopodon continues as polyphyletic, and only subgenera Leucophanella, Heliconema and Pseudocalymperes were recovered as monophyletic. The largest limbate subgenus Hyalolimbatae is polyphyletic with sampled taxa distributed among three separately supported clades. Divergence time analyses suggest a relatively recent (Mid to Late Miocene) radiation accompanying the spread of tropical forests coupled by multiple, independent pantropical exchanges. Although strong phylogeographic signal was recovered, multiple sister groups showed close geographical ties among Amazonian and Asian Pacific taxa suggesting that inter-continental migrations followed by cladogenic events occurred repeatedly starting from 20 mya. Evidence for inter-continental exchanges (i.e., long distance dispersal) in the relatively recent geological past is particularly unexpected for Calymperaceae as the family is dioecious (a rare trait for pantropical bryophytes), and characterized by low sporophyte production.

Crustose Stereocaulon species have only recently been reported from North America, and targeting them specifically in recent fieldwork revealed an unexpected diversity of species. We sampled crustose Stereocaulon species in western North America from Alaska to Oregon and analyzed them by morphology, DNA sequencing, and thin-layer chromatography. Five new species were found, along with one species known from northern Europe and North America (S. leucophaeopsis), a second one previously known only from northern Europe and eastern North America (S. plicatile), and one previously known western North American endemic (S. nivale). Each of these species is supported by DNA sequences, as well as morphological and chemical characters, such that they can be distinguished by simple spot tests and morphology. One exception is that S. leucophaeopsis and S. areolatum may be difficult to distinguish when sterile without a DNA sequence. The number of crustose Stereocaulon species known from North America is increased from 3 to 8. Seven of those eight species occur in the national parks of southwestern Alaska (Katmai, Lake Clark, and Kenai Fjords). Two of the eight are known from Oregon and Washington.

In the light of a phylogenetic reconstruction based on a multi-loci data set including sequence data from all three compartments (plastome: (rps4)–trnF, rpl16 group II intron; chondrome: nad5 group I intron; nuclear: ITS1&2) the Orthostichellaceae are described as a new family of pleurocarpous mosses. It is distributed mainly in the Neotropics and tropical Africa, and provisionally contains the genera Dixonia (Asia, 1 species), Afrothamnium gen. nov. (Africa and Neotropics, 1 sp.), Pinnatidendron gen. nov. (Africa and Neotropics, 1 sp.), Deslooveria gen. nov. (Africa and French Guiana, 5 spp.), Scabrellifolium gen. nov. (Neotropics and Africa, 2 spp.), and Orthostichella (Neotropics and Africa, 9 spp.). In the Neckeraceae we describe Dannorrisia gen. nov. (N. America, 1 sp.), Austrothamnium gen. nov. (Australasia, 2 spp.), and Bryobuckia gen. nov. (endemic to Chile, 7 spp.). Porotrichum s.str. becomes an essentially Neotropical genus and it contains the formerly recognized genera Porotrichopsis and Porotrichodendron. Thamnobryum s.str. is distributed exclusively in the Northern Hemisphere and is largely temperate. The mainly Macaronesian Echinodiaceae becomes a family of two genera, Echinodium (3 spp.) and Pseudomalia gen. nov. (1 sp.). The morphological evolution in the Orthostichellaceae is discussed based on the phylogeny.

Recent lichenological investigations of Fox Hills Formation sandstone outcrops in Colorado resulted in the discovery of three populations that represent an undescribed member of the Lecanora dispersa group (=Myriolecis). This new species is different from all others in the group in its production of usnic acid, which yields apothecia that are yellowish-green in color in fresh field material. The new species, here formally described as Lecanora lendemeri, is further characterized by its relatively large ascospores, endolithic thallus, presence of POL+ granules, and apparent restriction to this sandstone formation. We conducted molecular phylogenetic analyses to place the new species into the context of other members of Lecanora using new shotgun sequence data generated for this study in tandem with previously published rDNA data, and found that the new species is resolved as nested within the L. dispersa group, which was a strongly supported clade in our analysis. Using IUCN criteria including a known occurrence of only three populations, the largest of which is under conservation threat, we herein formally rank this new species as Endangered. This discovery comes on the heels of several other recent lichen discoveries on Fox Hills Sandstone, all species that are, so far as known, restricted to this rock type, suggesting that substrate endemism may be a common element of the biotic communities of the Fox Hills Formation. From the results of this and prior studies, it is clear that sandstone outcrops serve as important, yet still incompletely documented, habitats for cryptogamic diversity. This discovery further highlights the significance of conservation areas, even tiny units (e.g., 40 ha or less) that represent mere islands in a sea of urban development, such as in the Front Range of Colorado.

Biodiversity assessments are currently routine in most countries for measuring the impact of environmentally damaging projects. In order to properly document the species diversity occurring at a given locality, a fine understanding of the life history of each taxonomic group is needed. Thus, organism groups whose life cycle is poorly known may be overlooked in floristic assessments and underrepresented in natural history collections. This may lead to incomplete sampling and eventually inappropriate estimates of the local diversity and the extinction risks of certain taxa. Here, we study ephemeral bryophytes in central Chile semi-arid ecosystems. We selected Costesia macrocarpa, a Chilean endemic moss, as a model to demonstrate the consequences of omitting the life cycle information of a taxon when assessing its extinction risk, and for plant species diversity estimation in a given area. Based on winter sampling, we found that Costesia is not a vulnerable nor a nearly-threatened taxon, as has been previously suggested. Our findings reveal that it is ubiquitous throughout central Chile during the wet season, with no observed risk of extinction. These observations can be applied to several other little-known ephemeral bryophyte taxa found in central Chile.

Desiccation tolerance (DT) in poikilohydric organisms is dependent upon four principal sequential factors, (1) the rate of drying (RoD), (2) the water content (WC) of the organism deriving from the equilibrating relative humidity (RHeq), (3) the duration of the desiccation event, and (4) the rate of rehydration (RoR). The first two factors are often combined in experiments as the “intensity” of desiccation, and thus the effect of one on the other is relatively unknown but likely to be important ecologically. We hypothesized that more protracted rates of drying should mitigate damage at lower equilibrating RHs in a known inducibly DT species. Cultured uniclonal shoots of the moss Funaria hygrometrica were dried at different RoDs (time from full turgor to leaf curling, from 0.067 to 120 h) at five different RHs (12, 33, 54, 75 and 93%), allowed to equilibrate at each RH, rehydrated and assessed using chlorophyll fluorescence at 0.5 and 24 h postrehydration. At 24 h postrehydration, shoots of F. hygrometrica subjected to a rapid-dry event (<10 min) were unable to recover to control levels of fluorescence (F_v/F_m and Φ_PSII <80% of control levels) when equilibrated at RHeqs of ≤54%. Recovery was improved when the rate of drying was extended for more than ∼15 hours from full turgor to the onset of leaf curling at these RHeqs. When shoots were rapidly dried at RHeqs >54%, recovery was complete. At 0.5 h postrehydration, F_v/F_m levels indicated moderate damage at all RHeqs except 93%, with no mitigation of damage when the rate of drying was extended. Intensity of desiccation is normally construed as the ability to tolerate a combination of rate of drying × equilibrating RH. By varying the rate of drying across a range of RHeqs, F. hygrometrica is found to be able to tolerate all water contents tested, providing the rate of drying is extended to at least 15 h from full turgor to leaf curling. By adopting either the “step-down” approach to drying or the “wet substrate” technique used here, future studies on the desiccation tolerance of poikilohydric organisms can more accurately assess responses to desiccation stress.

Tropical regions harbor rich biodiversity but are relatively poorly explored, especially in lesser known taxonomic groups, such as lichenized fungi. In addition, the identification of species is complicated by frequent occurrence of cryptic species and the plasticity of phenotypic features traditionally used to identify species. Here, we aim to explore species diversity and provide tools for accurate sample identification of the genus Parmotrema from rainforests in Thailand. We gathered a three-locus DNA sequence data set and this was analysed in phylogenetic and DNA barcode frameworks. While some morpho-species were recovered as monophyletic, others did not form monophyletic groups. Our study unmasked cryptic lineages in Parmotrema species distributed in the tropics and show that phenotype-based sample identification may underestimate species diversity in this group of lichens. Further, genetic distances based on ITS DNA sequences (i.e. DNA barcode approach) were shown to be a valuable tool for sample identification. In addition, our study highlights the need for taxonomic reexamination of the following phenotypically delimited species: P. corniculans, P. crinitum, P. haitiense, P. maclayanum, P. perlatum and P. subtinctorium.

Drepanolejeunea robinsonii C.E.Zartman & A.M.Sierra is described and illustrated herein as a new species from the Amazon basin. The type collections are from lowland rainforest habitat in the central Amazon of Brazil. Morphological characters which distinguish the new species from the phenotypically similar Drepanolejeunea polyrhiza (Nees) Grolle & R.L.Zhu, are: 1) ovate leaf form; 2) conspicuously acute leaf apices; and 3) irregularly dentate to serrate teeth composed of 2–5 cells on leaf margins. Androecia were repeatedly observed on separate gametophytes suggesting the new taxon is dioecious, however neither gynoecia nor perianths have yet to be observed.

Micromitrium vazhanicum sp. nov. (Micomitriacecae), related to M. tenerum and M. austinii, is described from the Peechi-Vazhani Wildlife Sanctuary of the Western Ghats of Peninsular India. It is a tiny moss that grows in temporary ponds and moist muddy soil of the Moist Deciduous Forest of the Sanctuary. The minute leafy plants are barely identifiable in the field and grow in patches resembling filamentous green algal colonies. It is characterized by highly dome-shaped papillate persistent calyptra, spinose young spores and large mature spores (40–50 µm in diameter). The species is known to grow in highly unstable and undervalued habitats such as temporary ponds, which underscores the need for its conservation.

Bryoerythrophyllum sollmanianum J.A.Jiménez, M.J.Cano & Shevock is described and illustrated as a new species from the Sino-Himalayan region of China, Nepal and India. The species is corticolous, and easily distinguished from all its congeners in having stems with cluster of deciduous flagellate branchlets. Additionally, it is characterized by its lingulate leaves with apiculate apices, plane and regularly dentate margins above midleaf, costa ending below the apex, papillose basal cells that are not differentiated from the upper cells, and a rudimentary peristome. Its distinction from, and relationships with, similar species within the genus are discussed. Distribution of the new species is mapped.

Processes that shape biogeographic patterns in lichens have been of long-standing interest, especially in extreme environments. Lecideoid lichens in Antarctica have been relatively well-studied and are thought to have a high degree of endemism. However, recent collection efforts in montane regions of western North America have uncovered lecideoid lichens morphologically similar to some from Antarctic and South American Sub-Antarctic regions, including Lecidea andersonii Filson and L. polypycnidophora U.Rupr. & Türk. To explore the similarity between these putative conspecifics, we used ITS and MCM7 sequence data to infer relationships within a phylogenetic framework. The resulting phylogenetic reconstructions provided further evidence of the close relationship between specimens from western North America with geographically distant lecideoid populations in the Southern Hemisphere. We recovered two diverse, well-supported clades, provisionally called the L. andersonii complex and the ‘Lecidea NA-ARG clade,’ both including species-level subclades. A number of lecideoid species and species-level lineages thought to be endemic to Antarctica, the South American Sub-Antarctic region, or with bipolar distributions also occur in montane regions of western North America. In some cases, these species-level clades corresponded to distinct geographic regions, e.g., L. polypycnidophora, while other species failed to show phylogenetic structure corresponding to distinct geographic regions, e.g., L. andersonii. These findings bring into question the origin and prevalence of truly endemic Antarctic lichen-forming fungi. Additional investigations into lecideoid lichens, including the biogeographic connection between western North America with Antarctica, will likely provide novel perspectives into the connection between Antarctica and North America, potential colonization routes and the timing of dispersal events.

Photogrammetry, the use of photography to calculate measurements, includes a suite of algorithms known as Structure from Motion (SfM) that model 3D structure from standard photographic images. While use of SfM for objects or scenes at scales from centimeters to kilometers is common, studies that use macrophotography for small objects or scenes are few. This study tests methodology to optimize 3D modeling for change detection of lichen structure and community dynamics over time. Specifically, tests are performed to clarify uncertainties on software, photographic equipment, spatial control, making measurements, and the potential for accuracy and precision. Test subjects included common lichen communities on wood, bark and rock, plus a calicioid lichen community, each with two or three models over time. The commercial software PhotoScan outperformed the no-cost software alternatives VisualSfM and COLMAP. With PhotoScan, results of 3D modeling showed that while cellphone cameras are capable of producing models with sub-millimeter accuracy, DSLR cameras produce more accurate and detailed models. Photography using a narrow-angle macrolens demonstrated advantages over a wide-angle lens when working at this scale. Inclusion of a scaling object increased accuracy of spatial control relative to hand measurements. Detail and accuracy of models was sufficient to detect radial growth of a substrate tree and changes in calicioid ascomata that likely corresponded to humidity and provided evidence for hygroscopy in Chaenotheca. Models achieved accuracy as low as 0.06 mm root-mean-square-error (RMSE) and data density as high as 1.7 million points per cm² of substrate; accuracy was non-random and may be better described as local positional bias.