Rhizomnium punctatum Dotted Thyme-moss

A dioicous acrocarpous moss which grows in a variety of damp or wet shaded conditions on rocky or alluvial substrates along streams, tree roots, decorticated logs and swampy woodlands. The rather dense cushions of shoots covered with course rhizoids and the large, broadly elliptical leaves that are widest above the middle give this moss a very distinctive appearance. An important feature that can be seen with a hand lens is that the leaves are not toothed, they have a conspicuous nerve that ends just below the leaf tip and a border of elongated cells. Rhizomnium pseudopunctatum is similar but less common and has a close felt of slender rhizoids on its stems, which is not found on Rhizomnium punctatum. It is a very common species which is almost ubiquitous in Britain and is found throughout West Glamorgan. Sporophyte capsules are frequent in winter and spring. Gemmae produced on rather dense mats of protonema are also important for dispersal in drier habitats.