The phylogeny of the Dermatocarpon miniatum-complex (Verrucariales, lichenized Ascomycota) was studied using nuclear ITS sequence data by both parsimony and Bayesian inference of phylogeny. The ITS region contains a substantial amount of variation which resolves the relationships of terminal groups, while the more basal clades have low support in the analyses. D. miniatum var. miniatum and var. complicatum are polyphyletic, while var. cirsodes is monophyletic but located within the complex, as are both D. leptophyllum and D. linkolae. The variation within the D. miniatum-complex is significantly greater than that between some transatlantic species such as D. luridum and D. meiophyllizum. The new names D. taminium sp. nov. from the Greater Sonoran area, and D. tenue comb. nov. (syn. D. muehlenbergii var. tenue) are introduced.