Riccia glauca

HomeLearningSpecies FinderRiccia glauca

Identification notes

Riccia glauca is most commonly found in arable fields and in other disturbed places in the lowlands where there is some bare ground. It favours soils that are at least slightly acidic, being replaced in more basic habitats by R. sorocarpa. It is a short-lived species and is unlikely to be found on dry soils.

Of the 12 species in Britain and Ireland, just over half have a thallus surface that is entire i.e. not perforated in any way. Typical R. glauca has a distinctive blue-green colour although when individual rosettes are very small this may not be particularly obvious. R. sorocarpa is even more glaucous but it has a very well-defined median groove and abrupt edges to the thallus. The edges of R. glauca are not as sharp, but it lacks the swollen-looking margins of R. subbifurca, another species of acid soils.

Sometimes thallus sectioning may be needed to confirm Riccia species and a very sharp razor blade is strongly recommended. The image below shows parallel columns of cells in the upper side of the thallus, as well as a developing capsule, which, like all Riccia spp., develops wholly within the thallus.


Read the Field Guide account

Distribution in Great Britain and Ireland

View distribution from the BBS Atlas 2014