A short revision of the vagrant Aspicilia species of North America is presented based on morphological, molecular and ecological data. Vagrant Aspicilia are common lichens throughout the steppes of the western United States and in southwestern parts of Canada. Species delimitation of these lichens is difficult because of the paucity of morphological characters and large degree of variation. Inferences from nuITSrDNA sequences reveals that the North American specimens of A. fruticulosa are not most closely related to their Eurasian populations but instead share a unique ancestor with A. hispida. The specimens of A. fruticulosa from the New World are hereby recognized as a distinct species, A. rogeri. Its differentiation from the similar A. fruticulosa and A. hispida is discussed. The exclusion of A. fruticulosa from the N. American checklist is proposed temporarily.