Metzgeria furcata

Metzgeria furcata, the forked veilwort, is a frequent liverwort growing on the bark of a wide range of tree and shrub species and occasionally on rocks. It is a slim, translucent thallose liverwort forming yellow-green mats of branches about 1mm wide.
Description.
"Metzgeria furcata" has a midrib which is clearly visible over the rest of the thallus (which is 1mm wide), which also extends to the tip of the thallus, although without an excurrent nerve. The defining characteristic is definitely the fact that the thalli and the midrib fork at the end, which is visible on most patches. The Forked Veilwort rarely makes sporophytes, although on the underside of quite a few patches an inflorescence can be found.
British distribution.
Found over the whole of the British Isles, but less widely in Ireland and some parts of the Highlands. Found on Scilly, Shetland, Orkney and the Isle of Man.
Similar species in Britain.
"Apometzgeria pubescens" is very hairy and "Metzgeria fruticulosa" and "M. temperata" constantly have gemmae on the thalli. "M. conjugata" grows on rock, and "M. furcata" can sometimes grow on rock too, but "M. conjugata" has thalli that are twice as wide as "M. furcata" and the margins are much more turned down.