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Leucobryum is a moss genus that exhibits various bioactivities. However, the identification of Leucobryum species with morphology alone remains difficult. Chemical profile analysis provides additional tools for plant classification. This method uses chemical similarities to identify the differences among some plants, especially the different varieties of plant species. The objective of this study was to obtain the chemical profiles and use chemometrics to identify selected Leucobryum species found in Thailand. Lipophilic extracts from 18 samples of five taxa were analysed with thin-layer chromatography (TLC) and highperformance liquid chromatography (HPLC). Principal component analysis (PCA) and hierarchical cluster analysis were used to investigate the similarities of the chemical profiles. Permutational multivariate analysis of variance (PERMANOVA) was performed to determine the difference among taxa. The taxonomic identities were also verified with a molecular marker. Morphological and molecular identification were consistent for five taxa. The TLC profile could separate only the genus of the sample, while HPLC chromatograms showed separation among the Leucobryum taxa and consistent patterns within the same species. In addition, the chemical profiles of Leucobryum species were separated at the species level in PCA. The PERMANOVA showed significantly different profiles among the species (P value = 0.002). Therefore, this work illustrates the potential of chemometrics as supporting evidence for species delimitation in the moss genus Leucobryum. [ABSTRACT FROM AUTHOR]

Leucobryum aduncum is a moss species reported in many Southeast Asian regions, often found in forests with a high humidity. Climate change may impact the future distribution of this species. This study aimed to model the current distribution and predict the impact of climate change on L. aduncum distribution in the next 50 years across Southeast Asia. In the process, relevant climate variables in the distribution of the species were also identified. The occurrence data of this species with current and future climate models from CMIP6 under moderate (SSP2) scenarios were used to predict current and future L. aduncum distributions. Under the current climate, the predicted suitable areas for L. aduncum included most mountainous areas. However, many Southeast Asian areas showed a lower probability of finding this species in the next 50 years. The distribution area of this species will dramatically decrease by 50.16% in the current area. The most important ecological variables included the "mean temperature of the driest quarter" and the "annual temperature range". This study suggests the possible impacts of an increased temperature and the scale of climate change on the distribution of sensitive plants like bryophytes. [ABSTRACT FROM AUTHOR]

Leucobryum scalare was described in 1904 but its taxonomic status has been disputed, being reduced to a variety of Leucobryum aduncum or synonymized with Leucobryum aduncum. The taxonomic confusion of this taxon has remained unresolved. Hence, we revisited the taxonomic status of the taxon using phylogenetic and morphometric approaches. A total of 27 samples from Leucobryum aduncum var. aduncum and Leucobryum aduncum var. scalare were used to generate data from four markers, including ITS1, ITS2, atpB-rbcL spacer, and trnL-trnF. The concatenated dataset was used to reconstruct a phylogenetic tree. Both qualitative and quantitative morphological characters were measured and analyzed with Principal Component Analysis (PCA) and PERMANOVA. The results showed that the two taxa are closely related but they are reciprocally monophyletic. Both qualitative and quantitative characters could also separate Leucobryum aduncum var. scalare from Leucobryum aduncum var. aduncum as shown with PCA and PERMANOVA. We propose the resurrection of the species rank for Leucobryum scalare as separate from Leucobryum aduncum. This work highlights the need for a more thorough revision of Leucobryum to clarify the actual level of diversity in this genus. [ABSTRACT FROM AUTHOR]