Bilimbia fuscoviridis (≡ Bacidia fuscoviridis) is newly reported from North America where it is shown to be widespread in the temperate eastern United States and adjacent Canada, frequently occurring on shaded calcareous rocks and siliceous rocks in humid habitats near waterways. A detailed description on the basis of North American material is provided, the distribution is mapped, and color photographs are provided. The species is likely common but overlooked because of its inconspicuous appearance and the absence of diagnostic secondary metabolites. Key words: asexual reproduction, biodiversity, floristics, limestone, soredia, sterile sorediate crust.