A total of 46 species and two varieties of the traditionally interpreted genus Orthotrichum are currently known to occur in China. They represent five genera, including Orthotrichum (29 species), Lewinskya (14 species and two varieties), and Nyholmiella and Leratia that are represented by a single species each. The fifth genus Florschuetziella, also consisting of only one species, F. scaberrima, is an entirely neglected representative of the China’s moss flora. A list of all accepted taxa is presented and for each taxon all literature records and herbarium specimens are enumerated for provinces in which they have been recorded, and their distribution is mapped. A key to determination of Chinese orthotrichalean mosses is presented. A chronological list of 63 species and varieties and two designations, O. catagonioides and O. microsporum which have never been validly published, reported from China in the years 1892–2020 is presented. Four species, Orthotrichum brasii, O. hooglandii, O. elegans and O. gymnostomum are excluded from the bryoflora of China and Lewinskya affinis var. bohemica and Orthotrichum schimperi are recorded for the first time from this country. Phytogeography of the Chinese taxa of the orthotrichalean mosses is considered and they are grouped into eight phytogeographical elements and five sub-elements.

International audienceno abstrac

There is a large number of organisms in nature that are hard to find in the field, and one of these is also a rare bryophyte species, Buxbaumia viridis, which can also only be found in a certain part of the year in the production of sporophytes. Using distribution models, however, it is possible to predict the locations which this species is likely to be present at and to focus the field research directly on such sites. Thanks to the presented model, we have succeeded in identifying areas within the Czech Republic with an increased likelihood of its occurrence, even in some areas where no collection of B. viridis has so far been recorded. With the help of the maps created these locations can be identified with the accuracy of approximately 1 km2, making it easier for terrain research and resulting time and often financial expenses. We have also focused on the study of ecological factors that influence the occurrence of the species, and by testing variables from different categories we have come to some agreement with previously published studies. Whilst we have managed to exclude that air pollution has a major role to its occurrence, which has not yet been the subject of any study.

Orthotrichum pulchellum is a species of epiphytic moss in which a significant expansion from the oceanic part of Europe to the east of the continent has been observed in the recent two decades. The improvement in air quality in Central and Eastern Europe, but also climate change, probably plays a role in this. This study shows what direction of its spreading we can expect in the future. Ecological niche modeling (ENM) is a widespread method to find out species niches in environmental and geographical space, which allows us to highlight areas that have a higher probability of occurrences of the studied species, based on identifying similar environmental conditions to those already known. We also made predictions for different future scenarios (CMIP5 climatology datasets for the years 2041–2060). Because we were not able to distinguish between historical and newly settled areas, and so, had to use some of the traditional approaches when modeling invasive species, we proposed to use niche clusters based on environmental layers to split the data of all known occurrences and make models separately for each cluster. This approach seems reasonable from the ecological species point of view because using all the morphologically same samples could be misleading. Altogether, 2712 samples were used from three separate niche clusters. For building the models, the Maxent algorithm was used as a well-tested, well-accepted, and commonly used method.

<em>Lewinskya graphiomitria </em>(Müll. Hal. ex Beckett) F. Lara, Garilleti &amp; Goffinet, hitherto considered a New Zealand endemic species, has recently been repeatedly found at different localities in China, thereby representing an intriguing example of a remote intercontinental disjunction among the bryophytes. Herein, the current distribution of this species is reviewed and mapped and its disjunct occurrence in the two widely separated areas is discussed. Maps showing the quantification of extrapolated projection areas for <em>L. graphiomitria </em>are also presented. A possible way of its migration from New Zealand to Asia or vice versa is explained.