Rhabdoweisia crispata Toothed Streak-moss

A monoicous, acrocarpous moss which grows on acidic or slightly base-rich rocks on crags and in ravines. It is smaller than Rhobdowisia crenulata forming denser cushions with long narrow leaves that may have a few small teeth near the tip, but not conspicuously toothed as in that species. It is not easily distinguished from Rhabdoweisia fugax which has very narrow peristome teeth that are shed very quickly and both grow in similar habitats. It is a Suboceanic Boreal-montane species which has a similar western distribution to the other two Rhabdoweisia species in Britain but it is probably more widespread than either of them in Wales. It is absent from most of south Wales and in West Glamorgan it is only known from crags at Tan-y-Graig, Cwm Clydach and on slightly shaded, siliceous, rock ledges in the Nedd Fechan Valley. Sporophyte capsules are usually abundant throughout much of the year.