Identification notes
This species and C. calcarea are of similar appearance and habitat, although C. rossettiana has a more restricted distribution which includes southern England, where C. calcarea is unknown.
Once known, its pale green patches of densely interwoven shoots are eye-catching and conspicuously opaque due to its mamillose leaf cells, which scatter the light. Its shoots look more prickly under the hand-lens or stereomicroscope than C. calcarea but as the range of the two species overlaps in some places it’s always a good idea to collect a small sample (if there is enough) to confirm microscopically.
