Identification notes
This is a tiny liverwort with stems approx 0.25 – 0.5 mm across, generally rather inconspicuous if it were not for the usually bright green gemmae produced in abundance on the shoot apices which draw the eye in otherwise rather murky places. Its preferred habitat seems to be dark vertical peaty/muddy surfaces at the edge of tracks and paths. Damsholt’s Nordic liverwort flora describes it as growing in unattractive blackish places, “often over organic muck along reindeer paths”.
The concave subimbricate leaves are obliquely inserted and are bluntly bilobed to about 25%, but often less. Small lanceolate or bilobed underleaves are present, and like other members of the genus it produces leafless flagellae which can be difficult to find. 2-4 oil bodies are seen in the leaf cells of fresh material. The gemmae are angular and irregular, usually green but sometimes purplish, and indeed the leafy plant can sometimes appear purplish as well.
Plants without gemmae can be confused with Cephalozia bicuspidata which is a frequent associate. That plant has more deeply divided and sharply pointed leaves.
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