Pararistolochia deltantha 080101-1765
Sydney Botanic Gardens, in the Pyramid glasshouse (Australian natives).
This seems to be in flower every time I visit the Pyramid. Pararistolochia is distinguished from Aristolochia by its indehiscent fruit and 3-lobed flower. This species occurs in rainforest in far north-east Queensland, where it is a high-climbing liana.