Abstract
Thamnobryum cataractarum sp. nov. is described from Yorkshire, England. It is most closely related to T. fernandesii from Madeira and is also similar to T. angustifolium from Derbyshire, England. The three species are compared, and the habitat of the new species is described. T. fernandesii and T. cataractarum are retained in Thamnobryum rather than in Crassiphyllum Ochyra.