Cladistic analysis and revision of Billardiera (Pittosporaceae)

Abstract

Cladistic analyses of morphological data were used to clarify the definition of Billardiera in the context of other genera of the family Pittosporaceae. These analyses indicate that Billardiera s.str. is monophyletic including the small genera Sollya and Pronaya, but excluding Marianthus and Rhytidosporum, which have been previously included in a broader concept of Billardiera. The re-circumscribed Billardiera is revised, incorporating these changes. Five taxa are reinstated at species level (B. fusiformis, B. mutabilis, B. macrantha, B. speciosa and B. venusta). Three are new combinations (B. fraseri, B. heterophylla, B. drummondii replacing Sollya drummondii) and three new taxa are described for the first time: B. nesophila, B. rubens and B. viridiflora.