Ferns are plants with a free-living independent gametophyte generation; the type of breeding system may have substantial influence on the colonization rate of new habitat patches. Intragametophytic selfing allows establishment from a single spore, several spores originating from the same individual are required in the case of intergametophytic selfing, while intergametophytic crossing requires more dense gametophyte populations originating from different mature sporophytes (Lloyd 1974a, 1974b). Though additional research of the breeding system is needed, it has been supposed that Diellia ferns may represent intergametophytic crossing (Wagner 1952). This may be one possible cause for
the slow colonization rate of empty suitable habitat patches and rarity of the species.