Cladonia portentosa, also known as reindeer lichen or the cream cup lichen, is a light-coloured, fruticose, cup lichen in the family Cladoniaceae.
A similar-looking species, also known by the common name "reindeer lichen", is Cladonia rangiferina.
Cladonia portentosa forms compact interwoven mats up to 6 cm tall. It is richly branched, each branch usually dividing into three but with the penultimate sometimes dividing into two. The branching is at a larger angle than that of Cladonia rangiferina.[1]
As of July 2021, its conservation status has not been estimated by the IUCN. In Iceland, its conservation status is denoted as data deficient (DD).
Gilbert, O. 2004.[2]