Identification notes
Tortula muralis is one of those species that looks very different when moist and dry, and it is worth getting familiar with both. Hydrated leaves spread away from the stem and it’s easy to see their tongue-shaped form, with a silvery excurrent nerve. When dry, the leaves twist and curl, giving cushions a hoary appearance much like Grimmia pulvinata (with which it can grow). The leaves have quite an opaque, dull look about them, owing to the highly papillose leaf cells,
Fortunately sporophytes are normally present and greatly aid identification. They are borne on a long seta and when mature, have a beautiful spirally-twisted peristome.
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