Identification notes
Definitely one of the commonest Riccia species in most areas and fortunately it is also one of the easiest to recognise. Its glaucous green colour is distinctive, as is the deeply furrowed thallus, which looks like it has been scored with a knife blade.
Two good jizz characters can be seen at the edge of the thallus, which is sharply defined and has a narrow hyaline margin. Both serve to separate it from R. glauca, another blue-green species with which it sometimes grows.
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