Identification notes
In much of the country, this is the commonest of our three species of Pellia, although it is frequently replaced by P. endiviifolia on chalk, limestone or other highly basic rock.
Like P. neesiana and to a lesser extent P. endiviifolia, P. epiphylla can only be confidently identified in the field when reproductive structures are present. If they are, then you are home and dry, as P. epiphylla is our only monoicous species. Unless capsules are present search for the flap-like involucre (essentially the female bits) close to the end of the main thallus. If you can find this, look a little further back on the same thallus for a cluster of antheridial pits, (the males) which look like small sunken warts (see gallery photos below). If you can also find these, then you can be sure you have found P. epiphylla.
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