Introduction The Hyrcanian forests, located on the northern slopes of the Alborz Mountains, are deciduous lowland and montane forests harbouring a rich pleurocarpous moss flora. However, study of the bryoflora of this region is far from complete. The aim of the present study was to reveal the phylogenetic position of Taxiphyllum samples from the Hyrcanian forests of Iran and to compare these molecularly and morphologically with T. wissgrillii and T. densifolium.Methods Iranian Taxiphyllum samples were compared molecularly (based on nrITS and trnL-trnF) and morphologically with T. wissgrillii and T. densifolium.Key results Generated phylogenetic trees based on nrITS, trnL-trnF, and concatenated data showed a highly supported clade of Iranian Taxiphyllum accessions which is separate from a clade consisting of T. wissgrillii and T. densifolium. The molecularly studied samples from Iran are only tendentially large, with a relatively thick stem cortex, but the molecular differentiation is strong.Conclusions The strong molecular differentiation justifies the establishment of a new species. Therefore, Taxiphyllum hyrcanum is described as a new cryptic species. Owing to the lack of morphological and molecular differences between exemplars of T. wissgrillii and T. densifolium, we synonymise T. densifolium with T. wissgrillii.
Introduction Laos, which belongs to the Indo-Burma biodiversity hotspot, is one of the 14 tropical Asian plant-diversity darkspots. For bryophytes, it is one of the least known countries in the world. Here, we describe a new pleurocarpous moss species from karstic areas of Laos.Methods ITS and trnL-trnF sequences of a putative new species were generated and analysed within the context of the phylogeny of the Pylaisiadelphaceae. Its morphology was compared with that of congeneric species.Key results The new species is described as Trachyphyllum piliferum, sp. nov., on the basis of its sister relationship with T. jeyporense, based on both ITS and trnL-trnF datasets and morphological differences from other Trachyphyllum species. Trachyphyllum piliferum differs from the somewhat similar T. jeyporense by its larger size, more concave leaves that narrow more strongly towards their insertion and have a more clearly set-off twisted piliferous acumen, weakly dorsally prorate mid-leaf cells, and alar groups that extend further up along the leaf margins. Trachyphyllum piliferum occurs on karst in the Vang Vieng area. Entodontopsis anceps, E. wightii, Neckeromnion urocladum, Pelekium fuscatum, Philonotis hastata, Physcomitrium coorgense, Pseudosymblepharis subduriuscula and Taxithelium nepalense are new records for the moss flora of Laos.Conclusions The description of the new species, along with the report of eight new moss species records for Laos, illustrates the extent to which the bryophyte flora of the country is extremely poorly known. These results call for further research on the bryophyte flora of the Indo-Burma biodiversity hotspot.
Introduction Subtropical montane Sphagnum wetlands are threatened ecosystems, but the mechanisms structuring their bryophyte communities are poorly studied. We quantified the ecophysiological mechanisms driving the distribution of the key bryophyte species Sphagnum palustre L. and Polytrichum commune Hedw. Methods In China's Dajiuhu Wetland, we employed 32 1 m & times; 1 m quadrats to compare Sphagnum palustre and Polytrichum commune growth in bryophyte-monospecific (>90% cover of a single bryophyte) versus bryophyte-mixed stands (both species codominating the bryophyte layer). We measured vegetation, environmental factors, moss physiological traits, and soil physicochemical properties, using multivariate statistics to identify the key distribution drivers. Key results Each species performed optimally in its monospecific stands. In their two microhabitats within mixed-species stands, the height of Sphagnum palustre decreased by 24.2% and 33.2%, and its biomass by 31.6% and 36.8%, with no significant difference in capitula number. The number of shoots of Polytrichum commune decreased by 44.0% and 36.5%, and its biomass by 42.7% and 47.9%, with no significant height difference. Soil water content was the predominant environmental driver for S. palustre, while coverage of vascular plants dominated for P. commune. Physiologically, tissue water content and tissue K content were key for S. palustre, while soluble sugar, total chlorophyll, and tissue K content were key for P. commune. Conclusions Our study reveals a fundamental niche separation between these bryophytes mediated by distinct hydrological and light requirements, alongside species-specific nutrient limitations. Conservation strategies must prioritise hydrological integrity as the primary focus, with secondary interventions for canopy and nutrient management.
