Hornwort Species Research Articles

Liverwort (Marchantiophyta) and Hornwort (Anthocerotophyta) Flora of Yenice District (Çanakkale): New Floristic Findings from the Northern Part of Mount Ida (Kaz Dağı)

The Yenice district of Çanakkale stands out due to its diverse land features, being part of the Kaz Dağı (Mount Ida), its expansive coniferous and deciduous forests, and its potential for high biological diversity and endemism. It also provides highly suitable habitats for liverworts. However, the absence of legally protected areas highlights the need for a detailed assessment of the region's biodiversity. Liverworts are key components of floristic biological richness. Nevertheless, studies on the liverwort flora in both Çanakkale province and Yenice district are quite limited. Based on these considerations, this study aimed to investigate the liverwort flora of the Yenice district. During the study, a total of 295 liverwort specimens were collected from 74 different sites representative of the district’s various regions. The collected specimens were identified using appropriate methods and preserved as herbarium material. As a result of the study, 29 liverwort species from 17 families and 1 hornwort species were identified from the area. Of the identified species, 7 taxa are new records for the B6 grid square according to Henderson’s grid system (1961), and 13 taxa are new records for Çanakkale province.

Unique biogenesis and kinetics of hornwort Rubiscos revealed by synthetic biology systems

Hornworts are the only land plants that employ a pyrenoid to optimize Rubisco’s CO2 fixation. Yet, hornwort Rubisco remains poorly characterized. Here we assemble the hornwort Anthoceros agrestis Rubisco (AaRubisco) using the Arabidopsis thaliana SynBio expression system and observed the formation of stalled intermediates, prompting us to develop a new SynBio system with A. agrestis cognate chaperones. We successfully assembled AaRubisco and Rubisco from three other hornwort species. Unlike A. thaliana Rubisco, AaRubisco assembly is not dependent on RbcX or Raf2. Kinetic characterization reveals that hornwort Rubiscos exhibit a range of catalytic rates (3-10 s-1), but with similar affinity (∼30 μM) and specificity (∼70) for CO2. In other words, hornwort Rubiscos do not comply with the long held canonical catalytic trade-off observed in other land plants, providing experimental support that Rubisco kinetics may be phylogenetically constrained. Unexpectedly, we observed a 50% increase in AaRubisco catalytic rates when RbcX was removed from our SynBio system, without any reduction in specificity. Structural biology, biochemistry and proteomic analysis suggest that subtle differences in Rubisco large subunit interactions, when RbcX is absent during biogenesis, increases the accessibility of active sites and catalytic turnover rate. This study uncovered a previously unknown Rubisco kinetic parameter space and provides a SynBio chassis to expand the survey of other Rubisco kinetics. Our discovery could thus reshape the approaches for engineering Rubisco with superior kinetics.

Newly found and rediscovered hornworts (Anthocerotophyta) in Poland: Indicators of climate change impact in Central Europe.

In 2023, field research in south-western Poland led to the noteworthy discovery of two hornworts: Notothylasorbicularis, a species previously unrecorded in this country, and the rediscovery of Anthocerosneesii for the Polish bryoflora. These findings are significant as they suggest a response to climate change, which is facilitating the range expansion of hornworts within Central Europe. Detailed descriptions of the new localities for both species are provided, highlighting the specific environmental conditions and habitats where they were found. Distribution maps for Notothylasorbicularis and Anthocerosneesii in Poland are provided, as well as SEM micrographs of spores. Additionally, a key to the identification of Polish hornwort species is also included. Furthermore, a model projecting the potential future spread of these hornworts within Poland and the broader Central European region is presented. This model considers climatic variables and habitat availability, offering insights into possible range shifts. This study contributes to the growing body of evidence that climate change is a driving factor in the redistribution of bryophytes.

Predicting the spatial distribution of Turkish hornworts (Anthocerotophyta) under changing climatic conditions

Climate change is a phenomenon that can affect all living organisms. To see its effect, many methods and techniques have been improved recently. Species distribution modelling (SDM) is the most popular technique for this. Here, the distribution of hornworts (Anthoceros caucasicus, Anthoceros punctatus, Phaeoceros laevis and Phymatoceros bulbiculosus), which are a group of non-vascular land plants native to Türkiye, was studied under changing climate using SDM. Three global climate models (GCMs) (CMCC-ESM2, HadGEM3-GC31-LL and MIROC6), two scenarios (SSP1-2.6 and 5-8.5) and four time periods (2021–2040, 2041–2060, 2061–2080 and 2081–2100) were considered. A total of 89 occurrence records of the hornwort species A. caucasicus, A. punctatus and P. laevis were considered for SDM. The potential distribution of P. bulbiculosus could not be modelled due to a lack of sufficient coordinates. Although the patterns between current and future distributions did not change significantly, there were notable differences in the distribution of modelled species in the SSP 5–8.5 scenario. In particular, the MIROC6 model showed an anomalous pattern for A. punctatus in the SSP 5–8.5 scenario. The SDMs indicate that the model will be a valuable resource for the conservation of these species at local and regional levels throughout Türkiye.

Biolistics-mediated transformation of hornworts and its application to study pyrenoid protein localization.

Hornworts are a deeply diverged lineage of bryophytes and a sister lineage to mosses and liverworts. Hornworts have an array of unique features that can be leveraged to illuminate not only the early evolution of land plants, but also alternative paths for nitrogen and carbon assimilation via cyanobacterial symbiosis and a pyrenoid-based CO2-concentrating mechanism (CCM), respectively. Despite this, hornworts are one of the few plant lineages with limited available genetic tools. Here we report an efficient biolistics method for generating transient expression and stable transgenic lines in the model hornwort, Anthoceros agrestis. An average of 569 (±268) cells showed transient expression per bombardment, with green fluorescent protein expression observed within 48-72 h. A total of 81 stably transformed lines were recovered across three separate experiments, averaging six lines per bombardment. We followed the same method to transiently transform nine additional hornwort species, and obtained stable transformants from one. This method was further used to verify the localization of Rubisco and Rubisco activase in pyrenoids, which are central proteins for CCM function. Together, our biolistics approach offers key advantages over existing methods as it enables rapid transient expression and can be applied to widely diverse hornwort species.

Rosmarinic acid ameliorates the complications of monocrotaline-induced right ventricular hypertrophy on the left ventricle: Investigating the signaling pathway of Wnt/β-catenin in the heart.

Right ventricular hypertrophy (RVH) often results in failure of the right ventricle or even the left ventricle. Rosmarinic acid (RA), a natural polyphenol, is commonly found in Boraginaceae species and some species of ferns and hornworts. This study looked at how RA affects oxidative stress and left ventricular hemodynamic functions as well as RVH in monocrotaline (MCT) induced RVH model rats. To cause RVH, MCT (60 mg/kg) was intraperitoneally (IP) injected. Rats were given saline or RA (10, 15, and 30 mg/kg, gavage, over 21 days). In anesthetized rats, the lead II electrocardiogram was recorded. The hemodynamic functions of the isolated heart were measured using the Langendorff apparatus (at constant pressure). Investigations were made into the right ventricular hypertrophy index (RVHI), the activities of superoxide dismutase, catalase, glutathione, and Wnt and β-catenin gene expressions in the left ventricle. H&E staining was used. A significant decline in electrocardiogram parameters and anti-oxidant enzyme activities, an increase in QTc (Q-T corrected) intervals, MDA (Malondialdehyde), RVHI, and Wnt/β-catenin gene expression, and also significant changes in the hemodynamic parameters were demonstrated in the MCT group. RA improved the above-mentioned factors. According to the findings, RA may act as a cardioprotective agent against cardiovascular complications brought on by RVH due to its capacity to boost the activity of cardiac anti-oxidant enzymes and decrease the expression of genes involved in vascular calcification.

Red-list of liverwort and hornwort species of Serbia: 2024 assessment

The new extinction risk assessments of hornwort and liverwort species of Serbia have been completed. Based on the available data, 40% of Serbian liverwort flora is under threat (status 2024). Additionally, 11% of Serbian liverwort flora is considered to be Data Deficient (DD) 11% Near Threatened (NT). These findings clearly indicate the urgent need for field investigation and species biology research in order to define the major threats and adequate conservation measures.

On Recent Survey of Liverworts and Hornworts (Bryophyta) of Nagaland, India

The present paper provides an account of 61 taxa of liverworts and three hornwort species observed during recent survey of Nagaland.Out of these, 46 taxa (44 liverworts, 2 hornworts) are being reported for the first time from Nagaland. Cephaloziella herzogiana (Pandeand Srivastava) Udar and Kumar, and Porella caespitans (Steph.) S. Hatt. var. caespitans are reported as new to North-eastern India. FamilyPlagiochilaceae showed dominance with 14 species, followed by Lejeuneaceae with 9 species. Genus Plagiochila has maximum number(14) of species, followed by Frullania (5). In terms of habitat, corticolous liverworts are dominant as compared to terricolous and saxicolousspecies. In the present study key to all the taxa of Liverworts and Hornworts are also provided here along with habitat and distribution.

Liverwort and Hornwort Flora of Hoàng Liên National Park and the Adjacent Areas (North Vietnam, Indochina).

The study of the flora located in the central part of the Hoàng Liên Sơn Range in the northern region of Indochina has revealed 279 species of liverwort and hornwort, 26 of which are newly reported for the flora of Vietnam. The uniqueness and peculiarity of the studied flora are explained by the significant altitudinal range in the area treated and its position in the contact zone of the Sikang-Yunnan floristic province of the East Asian Floristic Region with the Indochina Floristic Region. The checklist includes data on the distribution of each species in the studied region, habitats, and accompanying taxa. The high disunity of the regional floras of the southern tip of the East Asian region compared to the lesser disunity of the regional floras in the north of the East Asian region is shown. In general, the studied flora possess Sino-Himalayan mountain subtropical characteristics with the large participation of tropical elements.

Geographical distribution of floating aquatic plants in relation to environmental conditions in southern Quebec, Canada

Communities of free-floating aquatic plants dominated by Lemnaceae (duckweeds) are common in ponds and wetlands globally with important ecological functions. In addition to the cosmopolitan common duckweed (Lemna minor), other species of Lemnaceae, liverworts (Ricciaceae), hornworts (Ceratophyllum), and water ferns (Salviniaceae) often coexist over broad geographic areas. Despite these species all sharing a similar mode of life and resource requirements, they have important morphological and physiological differences such as variation in body size, degree of morphological reduction, presence/number of roots, and position in the water column. The degree to which these differences play a role in shaping their distributions is, however, unclear. We report a field survey of floating aquatic plants in southern Quebec, Canada. We find that species distributions are influenced by habitat specialization to water phosphorus levels. High nutrient specialization followed a continual reduction in body size and morphological complexity, with smaller, simpler species found in higher nutrient sites. We also found a latitudinal gradient in species richness with more northerly sites supporting less diversity. Rare species did not show clustering suggesting that dispersal limitation was not an important factor in determining local abundance. Our results suggest that the distribution of these plants is in part driven by competitive sorting of suitable species from a regional species pool.

An optimized transformation protocol for Anthoceros agrestis and three more hornwort species.

Land plants comprise two large monophyletic lineages, the vascular plants and the bryophytes, which diverged from their most recent common ancestor approximately 480million years ago. Of the three lineages of bryophytes, only the mosses and the liverworts are systematically investigated, while the hornworts are understudied. Despite their importance for understanding fundamental questions of land plant evolution, they only recently became amenable to experimental investigation, with Anthoceros agrestis being developed as a hornwort model system. Availability of a high-quality genome assembly and a recently developed genetic transformation technique makes A. agrestis an attractive model species for hornworts. Here we describe an updated and optimized transformation protocol for A. agrestis, which can be successfully used to genetically modify one more strain of A. agrestis and three more hornwort species, Anthoceros punctatus, Leiosporoceros dussii, and Phaeoceros carolinianus. The new transformation method is less laborious, faster, and results in the generation of greatly increased numbers of transformants compared with the previous method. We have also developed a new selection marker for transformation. Finally, we report the development of a set of different cellular localization signal peptides for hornworts providing new tools to better understand the hornwort cell biology.

Differential Effects of Desiccation on Hornworts with Contrasting Life Histories in Tropical Montane Forests: A Functional Trait—Based Perspective

Desiccation tolerance (DT) is the ability of an organism or structure to dry completely and subsequently survive in that air-dry state. Hornworts are excellent plant models to study desiccation effects as they have contrasting life histories which are likely associated with DT. We tested whether (1) epiphytic species had more efficient DT responses to drying and postrehydration than non-epiphytic species and whether (2) “green” spores were more sensitive than non-green spores to extreme drying. Hornwort species were collected from the Atlantic Forest of Rio de Janeiro, Brazil. We studied five species (gametophytes and spores: Dendroceros crispus, D. crispatus, Nothoceros vincentianus, Phaeoceros carolinianus; and only spores of Anthoceros lamellatus), using different relative humidity values, drying durations, and postrehydration conditions. All DT treatments affected the chlorophyll fluorescence (Fv/Fm) of gametophytes, with species-specific responses. D. crispatus and D. crispus (epiphytes) performed better than P. carolinianus and N. vincentianus, with fast recovery of Fv/Fm values postrehydration. The ability of non-green spores of P. carolinianus and A. lamellatus and green spores of D. crispus to support desiccation led us to reject our second hypothesis. The DT strategies of hornworts highlighted the trade-offs that are important in spore dispersal and plant establishment, such as fast colonization in Dendroceros spp. and potential spore soil banks in Phaeoceros and Anthoceros species.

An Annotated Checklist of the Liverwort and Hornwort Flora of Nebraska

Listed by county are the currently known species of liverworts and hornworts collected in Nebraska. The list builds on the work of earlier collectors, especially that of Walter Kiener for the period 1936-1953. More recent collections include those by Locklear, Rolfsmeier, Steinauer, Sutherland, and Wikel. To date, hornworts and liverworts have been found in 67 of the state's 93 counties. The checklist provides county and collection information and brief notes on habitat preferences and diagnostic characters.

Cuticle structure and chemical composition of waxes in Phaeoceros laevis (L.) Prosk (Notothyladaceae, Anthocerotophyta).

The development of a hydrophobic cuticle covering the epidermis was a crucial evolutionary novelty ensuring the establishment of land plants. However, there is little information about its structure and chemical composition, as well as its functional implications in avascular lineages such as Anthocerotophyta. The main goal of the present study was to compare the gametophyte and sporophyte cuticles of Phaeoceros laevis. Semithin sections were analyzed through light microscopy (LM), cuticle structure was evaluated by transmission electron microscopy (TEM) and epicuticular wax morphology was analyzed by scanning electron microscopy (SEM). Total waxes were analyzed by CG/MS, and the components were identified based on the mass spectra. A thin lipophilic layer was detected on the sporophyte surface, structured as a stratified cuticular layer, similar to the well-known structure described for vascular plants. On the other hand, the gametophyte cuticle was observed only with TEM as a thin osmiophilic layer. SEM analyses showed a film-type wax on the surface of both life phases. The wax layer was eight-fold thicker on the sporophyte (0.8 µg cm-2) than on gametophyte (0.1 µg cm-2). Possible mechanical and/or drought protection are discussed. Fatty acids, primary alcohols, and steroids were identified in both life phases, while the kauren-16-ene diterpene (3%) was detected only on the sporophyte. Although no alkanes were detected in P. laevis, our findings unveil great similarity of the sporophyte cuticle of this hornwort species with the general data described for vascular plants, reinforcing the conservative condition of this character and supporting the previous idea that the biosynthetic machinery involved in the synthesis of wax compounds is conserved since the ancestor of land plants.

Modern Use of Bryophytes as a Source of Secondary Metabolites

Bryophytes constitute a heterogeneous group of plants which includes three clades: approximately 14,000 species of mosses (Bryophyta), 6000 species of liverworts (Marchantiophyta), and 300 species of hornworts (Anthocerotophyta). They are common in almost all ecosystems, where they play important roles. Bryophytes lack developed physical barriers, yet they are rarely attacked by herbivores or pathogens. Instead, they have acquired the ability to produce a wide range of secondary metabolites with diverse functions, such as phytotoxic, antibacterial, antifungal, insect antifeedant, and molluscicidal activities. Secondary metabolites in bryophytes can also be involved in stress tolerance, i.e., in UV-absorptive and drought- and freezing-tolerant activities. Due to these properties, for centuries bryophytes have been used to combat health problems in many cultures on different continents. Currently, scientists are discovering new, unique compounds in bryophytes with potential for practical use, which, in the age of drug resistance, may be of considerable importance. The aim of this review is to present bryophytes as a potential source of compounds with miscellaneous possible uses, with a focus on volatile compounds and antibacterial, antifungal, and cytotoxic potential, and as sources of materials for further promising research. The paper also briefly refers to the methods of compound extraction and acquisition. Formulas of compounds were drawn by the authors using ChemDraw software (PerkinElmer, Boston, MA, USA) with reference to data published in various papers, the ACD/Labs dictionary database, PubChem, and Scopus. The data were gathered in February 2022.

An updated checklist of liverworts and hornworts of Malaysia.

An updated checklist of the liverworts and hornworts of Malaysia accepts 773 species and 31 infraspecific taxa of liverworts, in 120 genera and 40 families, and 7 species of hornworts (6 genera, 3 families). The largest family is Lejeuneaceae with 312 species in 30 genera, accounting for 40% of the total number of species. The largest genera are Cololejeunea, Bazzania and Frullania with 90, 61 and 55 species, respectively. The greatest number of species has been recorded from Sabah with 568 species, followed by Pahang and Sarawak with 338 and 265 species, respectively.

A catalogue of the hornworts and liverworts of Croatia

Alegro, A., Šegota, V. & Rimac, A. 2021. A catalogue of the hornworts and liverworts of Croatia. – Herzogia 34: 227–254. The amount of information on the hornwort and liverwort flora of Croatia has increased in the last decade due to new field records and detailed literature reviews. Based on these data, an updated list of the hornwort and liverwort taxa present in Croatia has been compiled and is presented here. Considering recent taxonomic and nomenclatural changes, five hornwort species, 156 liverwort species and seven infraspecific taxa are reported for the country. Additionally, 16 taxa are rejected with explanatory annotations. For each taxon, all the publications in which it is cited are listed in chronological order, along with the nomenclature originally used.

A review of frameworks for using bryophytes as indicators of climate change with special emphasis on Sri Lankan bryoflora.

The tropical island of Sri Lanka, with a land area of 65,610 km2 and 1340 km of coastline, is highly vulnerable to impacts of climate change, with detrimental effects on agriculture, water resources, human health, coastal zones, infrastructure, industry, and biodiversity. A general increase in temperature and precipitation patterns, rising sea levels, and increase in weather-related natural disasters, such as floods and droughts, have been traced over the years. Bryophytes (liverworts, mosses, hornworts) occupy a pivotal position in the land plant evolution and form a unique part of the vegetation. Many taxa of bryophytes exhibit observable, distinct adaptations in response to changes in environmental conditions quickly. Bryophytes can be used to monitor climate change in two ways; (i) presence or absence in the ecosystem and (ii) changes in morphology and physiology that can be used for monitoring. Sri Lanka has a rich bryophyte flora consisting of 575 species of mosses, 338 species of liverworts, and 07 species of hornworts. It is estimated that 11% of mosses are endemic; there are no endemic thalloid liverworts or hornworts found in Sri Lanka, and the endemicity of leafy liverworts is yet to be investigated. The taxonomic status of endemic taxa and the biogeographic affinities of many taxa remain unexplored. Further, the potential use of bryophytes as indicators of climate change in Sri Lanka has not yet been investigated. This paper compiles the information on morphological and physiological responses of bryophytes to elevated temperature, increase in greenhouse gases, increased ultraviolet-B (UV-B) radiation, and fluctuations in humidity. In the light of this gathered global knowledge, possible species of bryophytes to be used in assessing and predicting climate change and developing a climate change model in Sri Lanka are proposed. Asian bryophytes, in general, have poorly been represented in climate change literature. We believe that this knowledge will form the foundation for future research focused on climate change mitigation in other tropical and Asian countries.

A quick glance at noteworthy articles for September 2021

A quick glance at noteworthy articles for September 2021

The diversity and community structure of symbiotic cyanobacteria in hornworts inferred from long-read amplicon sequencing.

Nitrogen-fixing endosymbioses with cyanobacteria have evolved independently in five very different plant lineages. Expanding knowledge of these symbioses promises to improve the understanding of symbiosis evolution and broaden the toolkit for agricultural engineering to reduce artificial fertilizer use. Here we focused on hornworts, a bryophyte lineage in which all members host cyanobacteria, and investigated factors shaping the diversity of their cyanobiont communities. We sampled hornworts and adjacent soils in upstate New York throughout the hornwort growing season. We included all three sympatric hornwort species in the area, allowing us to directly compare partner selectivity. To profile cyanobacteria communities, we established a metabarcoding protocol targeting rbcL-X with PacBio long reads. The hornwort cyanobionts detected were phylogenetically diverse, including clades that do not contain other known plant symbionts. We found significant overlap between hornwort cyanobionts and soil cyanobacteria, a pattern not previously reported in other plant-cyanobacteria symbioses. Cyanobiont communities differed between host plants only centimeters apart, but we did not detect an effect of sampling time or host species on the cyanobacterial community structure. This study expands the phylogenetic diversity of known symbiotic cyanobacteria. Our analyses suggest that hornwort cyanobionts have a tight connection to the soil background, and we found no evidence that time within growing season, host species, or distance at the scale of meters strongly govern cyanobacteria community assembly. This study provides a critical foundation for further study of the ecology, evolution, and interaction dynamics of plant-cyanobacteria symbiosis.