The term rheophyte describes a biological group of flood-tolerant plants that are confined to the beds of swift-running streams and rivers in nature and grow up to flood level, but not beyond the reach of regularly occurring flash floods. Although over 35 yr have passed since the first global census of rheophytes, no updates have been recorded regarding the number of taxa in this biological group in seed plants. Therefore, the present work aimed to (1) review the main topics associated with rheophytism (e.g., morphological characteristics, genetic studies, geographic distribution, conservation, and evolutionary aspects); (2) provide an updated checklist of rheophytes distributed around the world considering the two main groups in seed plants (gymnosperms and angiosperms); (3) demonstrate the distribution of rheophytism in the angiosperm phylogeny; and (4) estimate the geographical distribution and richness of selected taxa on the world map for the first time. All data compiled for the present study originated from a search of peer-reviewed articles, secondary literature (theses, dissertations, reports, books, and floras), and electronic facilities. We compiled a data set composed of four taxa in gymnosperms (Podocarpaceae family) and 1,368 taxa (including obligate, facultative, and unclassified rheophytes) distributed in 114 families and 508 genera in angiosperms. Most of the studied taxa belong to eudicotyledons (72.81%), while 1.46% belong to magnoliids, and 25.73% belong to monocotyledons. The families with the highest number of taxa in descending order are Podostemaceae, Araceae, Myrtaceae, Rubiaceae, Asteraceae, Apocynaceae, Arecaceae, Fabaceae, Phyllanthaceae, and Poaceae. Of the 114 families plotted in angiosperm phylogeny, at least 80 harbor obligate rheophytes. The geographical distribution of rheophytes in angiosperms, as expected based on the first census of this biological group, is mainly in the tropical and subtropical regions. The high richness of rheophytic taxa was mostly found in southern Mexico, southern China, Borneo, and northern and eastern Australia. In contrast, the geographical distribution of rheophytes in gymnosperms is restricted to New Caledonia and Tasmania. The present study will help to advance knowledge regarding the diversity of rheophytes in angiosperms and gymnosperms while drawing attention to this biological group, which has often been overlooked. There are no copyright restrictions. Please cite this data paper when the data are used in publications and teaching events.
Keywords: angiosperm phylogeny; angiosperms; distribution; gymnosperms; rheophyte; rheophytic; rheophytism; species richness.
© 2020 by the Ecological Society of America.