ABSTRACT Introduction In recent years, four small amblystegiaceous mosses have been discovered and described as new. Despite their morphological similarity with Serpoleskea or even the phylogenetically unrelated Heterocladium or Platydictya, molecular data have confirmed their affinity with Amblystegiaceae and supported their recognition in two new genera, Arvernella and Microamblystegium. Methods We analysed the sequences of nuclear (ITS and gpd) and plastid (trnF–trnS, trnK and atpB–rbcL) regions to assess the phylogenetic affinities of an originally unidentified amblystegiaceous moss recently collected in Saxon Switzerland (Saxony, Germany). In the light of the results from the molecular analysis, the moss was compared morphologically with the types of Microamblystegium saxicola and Platydictya hattorii. Key results The sequences of the analysed specimen from Saxon Switzerland showed a full identity with the published sequences of Microamblystegium saxicola. The morphological comparison of the newly found plant also largely confirmed this result. Additionally, the plants agree morphologically with the type material of Platydictya hattorii. The reassessed phylogenetic affinities of Microamblystegium now support the sister-group relationship between this moss and the remaining Cratoneuron-related genera. However, the affinities assessed on gpd sequence data provide an alternative phylogenetic hypothesis to both the ITS-based and plastid-based phylogenies at several internal nodes within Amblystegiaceae. Conclusions Morphological and molecular data confirmed the unexpected identity of the plant from Germany with Microamblystegium saxicola, recently described from far-eastern Asia. This species is shown to be morphologically identical to Platydictya hattorii, previously known only from Japan, and this necessitates the new combination Microamblystegium hattorii.

ABSTRACT Background Terrestrial plants play a crucial role in the biogeochemical silicon cycle, acting as a major sink for biogenic silica (BSi). While silicon uptake in vascular plants is well studied, less is known about its occurrence in non-vascular plants. Previous research found silicon uptake, biomineralisation and BSi deposits in bryophyte tissues, suggesting a role in silicon cycling, but did not identify uptake drivers. Methods The present study examined the responses of Marchantia polymorpha L. to two potential drivers: silicon fertilisation and soil water content. Marchantia polymorpha was grown on natural loamy-sandy soil with different dunite (silicon-rich igneous rock) grain sizes (coarse or fine) and exposed to weekly or daily precipitation regimes. A control without dunite was subjected to the same regimes. After 30 days, three types of organ (thalli, antheridiophores and archegoniophores) were sampled and analysed colorimetrically for BSi. Key results All organs contained BSi, with antheridiophores showing the highest concentrations (0.31–1.77 mg/g dry weight). Fine (vs coarse) dunite reduced BSi content in all organs. No difference in BSi was found between coarse dunite and the control. Precipitation regime had a significant effect only in the controls: weekly precipitation (vs daily watering) increased BSi concentrations in all organs. Conclusions The study confirms that Marchantia polymorpha absorbs dissolved silicon and deposits it as BSi in its tissues, with deposition varying by organ – results consistent with previous findings of higher BSi in antheridiophores. Silicon fertilisation and soil water content drive silicon uptake in liverworts, similarly to in vascular plants.

ABSTRACT Introduction This article provides a detailed analysis of the spore morphology and ultrastructure of Alophosia azorica (Renauld & Cardot) Cardot, a Macaronesian endemic moss of the family Polytrichaceae, reviews its morphological characters, and clarifies its life strategy. Methods The specimens used in this study came mainly from the bryophyte sections of the herbaria of the University of the Azores (AZU) and the University of Lisbon (LISU), with fresh samples also collected in the field. Observations were made and measurements taken of the stem, leaves, rhizoids, capsule and setae, for comparison with published reports. Sporophytes from five specimens of Alophosia azorica were separated to study spore morphology using light and scanning electron microscopy. Key results and conclusions The specimens investigated in this study exhibited the typical characteristics assigned to the species in previous studies. The examined spores are isomorphic monads, heteropolar with a subcircular amb, spheroidal in polar view, convex-plane in equatorial view, with psilate exospore and presence of a perispore with microechinate ornamentation, and are very small. Alophosia azorica is considered a colonist sensu stricto due to its small, abundant spores, the production of sporophytes across two seasons, and the presence of asexual propagules, indicating a moderate reproductive effort.

ABSTRACT Introduction Similarly to tracheophytes, bryophytes benefit from zoochory as a mechanism for their dispersal, although this is not species specific or well explored. To address this knowledge gap, we investigated whether earthworms can facilitate bryophyte dispersal. Methods The selected species represented distinct bryophyte characteristics, allowing us to investigate trait-specific responses to earthworm-mediated dispersal. We subjected three bryophyte species (Chryso-hypnum diminutivum, Fossombronia porphyrorhiza and Hyophila involuta) to two treatments: bryophyte dust and bryophyte squares. Key results Our observations showed bryophyte growth in 47% of the sampled units, thus supporting our initial hypothesis. Hyophila involuta emerged as the top-performing species, with the bryophyte dust treatment providing the highest efficacy. This controlled experiment provides evidence supporting the hypothesis of bryophyte dispersal by earthworms. Conclusions The observed efficacy of bryophyte dust is probably due to the ease with which small plant fragments are ingested by the worms. This suggests a potential ecological role for earthworms in the dispersal of bryophytes in natural settings.

ABSTRACT Introduction The Macaronesian endemic pleurocarpous moss genus Echinodium comprises three species: E. renauldii (Azores), E. setigerum (Madeira) and E. spinosum (Madeira, Canary Islands). While the generic circumscription of Echinodium has been clarified, species delimitation and relationships, as well as patterns of intraspecific variation, remain insufficiently known. Methods We analysed intra- and interspecific differentiation of all three Echinodium species based on phylogenetic reconstructions of DNA sequence data from all three genomes, haplotype networks, and principal coordinates analysis of AFLP fingerprinting data. Key results The Echinodiaceae and Echinodium were resolved as monophyletic. In line with morphological differences, all three Echinodium species were distinguishable from each other. Molecular and morphological data suggested two conflicting relationships, with either E. setigerum and E. renauldii or E. spinosum and E. renauldii being closer to each other. Intraspecific molecular variation, observed in all three species, reflected the geographical isolation of populations, between Madeira and the Canary Islands, the western and central island groups of the Azores, and valleys on Madeira Island. Conclusions The molecular data support recognition of three Echinodium species. The patterns observed of molecular and morphological variation do not yet permit conclusions about the relationships and evolutionary origin of these species. Despite the clear geographical separation, the genetic similarity of some western and central Azorean populations may result from dispersal events. Our study adds to accumulating support for a biogeographical distinction between the Azores and Madeira/the Canary Islands for Macaronesian endemic pleurocarpous mosses, which is visible at either the species or intraspecific level.

ABSTRACT Introduction Marchantia longii R.L.Zhu, Y.L.Xiang & L.Shu is one of the few novel taxa of Marchantiaceae published since 2000. Taxonomic knowledge remains scant, as it is known solely from its type collection. Methods Type specimens of Marchantia longii and M. formosana Horik. were examined, using dissecting and optical microscopes. Further specimens of M. longii, collected during our recent field trip to Dulongjiang, Yunnan, China, the type locality of this species, were additionally referenced. Molecular phylogenetic analysis was performed using the same molecular markers as for the protologue of M. longii. Key results The morphological characteristics of the plant described as Marchantia longii fell within the range of plasticity in M. formosana. Phylogenetically, both species were resolved into the same monophyletic clade, exhibiting very little molecular difference, thus supporting M. longii as a new synonym of M. formosana. Marchantia formosana, previously thought to be endemic to Taiwan, was shown to have a wider distribution, reaching into inland China.

ABSTRACT Methods. Morphological study and DNA sequencing (ITS, rps4) were carried out using Bryoerythrophyllum specimens collected in the Asir and Mecca provinces of Saudi Arabia, and the results compared against published data for B. duellii. Key results. The Arabian plants match Bryoerythrophyllum duellii in diagnostic morphology, although with more frequent spinose marginal teeth and occasional apiculi. The rps4 sequence was identical to that of Greek and Cypriot accessions; the ITS sequence differed by only a few substitutions and indels, clustering with strong support in a monophyletic B. duellii clade. The species was found at 2100–2500 m on granitic substrates in clearings within Juniperus procera woodland, extending the known range nearly 2000 km southeast and representing the first record of Bryoerythrophyllum in the Arabian Peninsula. Conclusions. Our morphological and molecular findings confirm the identity of the Saudi Arabian plants as Bryoerythrophyllum duellii. The discovery highlights its wider biogeographical potential and the need for habitat management to mitigate grazing impacts.

ABSTRACT Introduction. Macromitrium giraldii Müll.Hal. was previously considered a synonym of M. japonicum Dozy & Molk. Our ongoing research on the genus Macromitrium Brid. has enabled us to identify morphological differences between M. japonicum and M. giraldii, as well as a close similarity between the latter and the widely distributed East Asian M. cavaleriei Cardot & Thér. Here we present morphological and phylogenetic evidence supporting our speculation that M. giraldii and M. cavarleriei are conspecific, and that the former should be recognised. Methods. A morphological study of the original material of Macromitrium giraldii, M. cavaleriei, M. japonicum and their accepted synonyms was conducted, including recent specimens matching their descriptions. A phylogenetic analysis based on the nuclear ITS2 and the plastid trnL–F and trnG regions was performed to investigate relationships within the genus. Key results and conclusions. The morphological and phylogenetic data support Macromitrium giraldii and M. cavaleriei as conspecific, with similarities observed in their branch leaves. All previously accepted synonyms of the latter are additionally confirmed to be M. giraldii. We here propose to synonymise these two species as M. giraldii, since this name has priority. Consequently, M. giraldii is distributed throughout China, as well as in Japan, South Korea, Vietnam, Nepal and India.