Cladistic analysis and revision of 'Billardiera' (Pittosporaceae)

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'.