Frullania heinrichsii (subg. Chonanthelia sect. Cladocarpicae) is newly described from Peru. The new species is characterized by its robust size, undulate leaf margins, undivided underleaves with strongly auriculate bases, autoicous sexuality and 4-keeled perianths. The species has morphological affinities with F. holostipula, F. obscura and F. rio-janeirensis, blurring the subsectional classification boundaries between these species. As a result, subsect. Holostipulae and subsect. Quadriplicatae are proposed as synonyms of sect. Cladocarpicae. Frullania holostipula, hitherto only known from Venezuela, is newly reported from Bolivia. An updated key is provided to the thirteen species recognized in sect. Cladocarpicae.