We conducted a systematic revision of the genus Loxsomopsis H. Christ (Loxomataceae) based on 99 herbarium sheets representing about 52 separate gatherings. Many morphological characters varied considerably, but as much of this variation was found within individual collections it was of little taxonomic relevance. Characters that varied between specimens but remained roughly constant within individual gatherings included the pubescence of lamina, petiole, and sorus, hair size and coloration, presence or absence of glaucous layers on the lamina surface, and spore surface structure. However, we found no correlation in the occurrence of two or more of these characters and were unable to morphologically define discrete species within the genus. Thus, we consider Loxsomopsis to include one variable species, L. pearcei (Baker) Maxon. The morphological variation is probably the result of the distribution of the species in small, isolated populations in ephemeral early successional habitats, leading to continuous population extinction and establishment of new population based on few propagules. Notes on ecology and distribution, full taxonomy, and specimen citations are provided.