The systematic position of Microlejeunea ocellata (Marchantiophyta: Lejeuneaceae), an extraordinary species endemic to Australia and New Zealand

Microlejeunea ocellata (Herzog) Grolle was originally recognized as Rectolejeunea ocellata Herzog, a very enigmatic species known only from Australia and New Zealand. The systematic position of this species has been controversial owing to a number of interesting characters. A monospecific subgenus, Rectolejeunea subg. Notholejeunea R.M.Schust. was previously established to accommodate this species. Our molecular phylogenetic and morphological evidence reveals that this species represents a separate genus. Here we propose a new generic name, Cumulolejeunea, because recombining subg. Notholejeunea R.M.Schust. at generic rank is blocked by the earlier Notholejeunea Kuntze of 1903.