Roccella Tinctoria is a lichen species that has been used for centuries in the dying of textiles. It is commonly known as orchil and can be found on rocks and trees in coastal regions. However, there are several synonyms for Roccella Tinctoria, including Lecanora tinctoria and Ochrolechia tinctoria. These synonyms refer to the same species of lichen that produce a purple dye when processed correctly. Other synonyms for Roccella Tinctoria include litmus lichen, orchil weed, and cellaure. These terms are often used in different contexts but all refer to the same type of lichen that has been valued for its dyeing properties for centuries.