Cryptothecia aleurodes was considered to be a widespread, rare tropical lichen having white ascigerous areas and a crustose whitish-grey thallus containing norstictic acid. A revision of its type specimen from Guadeloupe and the study of recent specimens from Martinique proved that the species has been misunderstood. In this paper, Cryptothecia aleurodes is shown to have a K– and C+ red thallus containing notably gyrophoric acid as major secondary metabolite but lacking norstictic acid. A detailed description and illustrations are provided. The species is known with certainty only from the Caribbean and has probably a Neotropical distribution. Previous reports of C. aleurodes from the Seychelles and Thailand are shown to be misidentifications and reports from India are considered dubious.