Cup lichens are a large lichen genus that consists of over 270 species. Cup lichens are upright-growing fruticose lichens whose podetia vary in shape and size. Most often cup lichens are hollow and tubular. They can be branchless or multi-branched and cup-like, blunt or stick-like at the top.

Most cup lichens grow on the ground but some can also grow on deadwood or as epiphytes on trees. They are found almost everywhere in the world. There are approximately 60 different cup lichen species in Finland.

Reindeer moss belong to the cup lichen genus. Reindeer moss are the main food for domestic and wild reindeer. Cup lichens have been used for dyeing wool.

Some cup lichens are very common while some are critically endangered. Thus conservation measures have to be considered according to the species. For the endangered species it is important to secure the key features of their habitats.