Lendemer, J. C. 2011: A review of the morphologically similar species Fuscidea pusilla and Ropalospora viridis in eastern North America. - Opuscula Philolichenum9: 11-20. [RLL List # 223 / Rec.# 32914] Abstract: The distinguishing features of Ropalospora viridis and Fuscidea pusilla are discussed. The geographic distributions of the two species in eastern North America are revised: although both species have an Appalachian-Great Lakes distribution they have somewhat differing biogeographic tendencies. Fuscidea pusilla is a rare species of the northern boreal forests with disjunct populations in the central Appalachian Mountains, whereas R. viridis is common and widespread throughout the Appalachian Mountains and their outliers with disjunct populations in the Great Lakes. Color illustrations of both species are provided