What does "roccella" mean?

Any of a group of lichens of genus Roccella, especially Rocella tinctoria from which litmus is extracted.

Roccella

Common synonyms include: genus, lichen genus, lichen group, orchil dye source, orchil lichen, orchil producer.

noun

noun ·Rare ·Advanced level

Noun

1
Any of a group of lichens of genus Roccella, especially Rocella tinctoria from which litmus is extracted.
2
a source of the dye archil and of litmus wordnet

From the genus name.