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Rhytidiadelphus (order Hypnobryales) A genus of large, robust mosses in which the shoots are erect to procumbent. The stems are usually long, and irregularly to pinnately branched. The leaves are broad at the base, gradually or abruptly narrowing to a sharply pointed tip; each leaf may have a short double nerve, or it may be nerveless. The seta is deep red and smooth. There are about 8 species, mainly found in northern temperate regions, and including some attractive British species. R. triquetrus is often conspicuous, with tall, tough, erect stems from which branches arise irregularly to give a bushy habit; the leaves are large and spreading, and capsules are rarely formed. It is found mostly in woodland clearings. R. squarrosus is a smaller moss with squarrose leaves; the shoot apices have a characteristic star-like appearance. It is found in moist grassland and is a common weed in lawns.