AbstractThe genusThamnobryumis reviewed from Macaronesia (excludingthe Cape Verde Islands). In this area there are three species,T. alopecurum(Hedw.) Gang.,T. maderense(Kindb.) Hedenäs,comb. nov.andT. fernandesiiC. Sérgio.T. fernandesiiis only known from Madeira; the other two also occur on the Canary Islands and the Azores.Thamnobryum canariense(Ren.&Card.) Long is transferred toIsothecium,asI. atlanticumHedenäs,comb. et nom. nov.