Please read the introduction first page in this scholarly publication: https://www.researchgate.net/profile/Greg-Keighery/publication/355844429_From_Field_and_Study_Opening_Pandora's_Box_Pandorea_Bignoniaceae_in_Western_Australia/links/6180f918a767a03c14e29b6b/From-Field-and-Study-Opening-Pandoras-Box-Pandorea-Bignoniaceae-in-Western-Australia.pdf
Extracted point quotation: " ... Continuing taxonomic studies mainly in Queensland, have shown that the broad species concept of van Steenis (1977), who recorded six species in the entire genus, needs considerable revision. ... " . .