Among the Campyloneurum that occur entirely or primarily in the Atlantic Rain Forest of Brazil, three species have been previously referred to by the following six names: C. acrocarpon, C. crispum, C. herbaceum, C. lapathifolium, C. minus, and C. wacketii. We show that C. crispum and C. herbaceum are the correct names for two of the species, and we designate lectotypes for these two names. The third species, which ranges from Brazil to Argentina and Paraguay, lacks a name and is here newly described as C. atlanticum. Two of the previously used names, C. acrocarpon and C. wacketii, are considered synonyms of C. crispum. The remaining names, C. lapathifolium and C. minus, appear to be of uncertain application. Based on our field studies, C. atlanticum and C. herbaceum are primary hemiepiphytes. Our finding constitutes the first report of this growth habit in the genus. The third Brazilian species treated herein, C. crispum, varies in growth habit, being either terrestrial, primary hemiepiphytic, or holoepiphytic. The spores of the three species are uniform and typical of the genus; they do not provide any distinguishing characters for the species.