Supposedly endemic to Papua New Guinea (Hattori & Pippo 1986).
Notes: Known only from the type collection (Hattori 1988). The drawings and description are scant, but further investigation may lead to the conclusion that this taxon be recognised at the rank of species. This taxon has very distinctive short-cylindrical projections dispersed on the dorsal surface of the leaf lobe (Hattori 1988). From what can be interpreted from the drawings, these projections appear similar to those described for an otherwise morphologically very different species, F. hattorii, described by von Konrat & Braggins (2003) of subg. Microfrullania. In F. hattorii, the protuberances are uniformly distributed across the surface of the dorsal lobe with each cell bearing one conical protuberance. In contrast, the protuberances are scattered in a seemingly random pattern in F. dentata. var. secernens where some cells do not bear a protuberance.