Pottiopsis gen. nov. and notes on other taxa of British and Irish Pottiaceae

Abstract A new genus, Pottiopsis is described to accommodate Pottia (Trichostomum) caespitosa. Two new combinations are made: Tortula viridifolia (=Pottia crinita) and Weissia controversa var. wimmeriana (= W wimmeriana). Weissia controversa var. crispata is shown to be a valid name. British Didymodon reedii is shown to be a form of D. vinealis.