Part of its flora is inherited from the ancient supercontinent of Gondwana or exchanged later (e.g. Piperaceae with pantropical distribution and but few warm temperate representatives).
These Gondwanan lineages are related to those in the Neotropical kingdom, composed of the tropical areas of Central and South America.
A distinct community of vascular plants evolved millions of years ago, and are now found on several separate areas.
Millions of years ago, the warmer and wetter areas supported a tropical adapted flora, including forests of podocarps and southern beech.
Although warm cloud forests disappeared during the glaciations, they re-colonized large areas every time the weather was favorable again.
Many members of the late Cretaceous–early Tertiary Gondwanan flora survived in islands and Coastal area's equable climate but were eliminated in mainland due to increasingly dry conditions.
For example, genera, Archeria in Ericaceae, or Wollemia in the family Araucariaceae, was known only from fossil remains before the discovery of the living species in 1994 in a temperate rainforest wilderness area of the Wollemi National Park in New South Wales, in a remote series of narrow, steep-sided sandstone gorges near Lithgow.
The paleotropical flora is characterized by about 40 endemic plant families, the most famous being Nepenthaceae, Musaceae, Pandanaceae and Flagellariaceae,[2] but including also Matoniaceae, Dipteridaceae, Stangeriaceae, Welwitschiaceae, Degeneriaceae, Rafflesiaceae, Didiereaceae, Didymelaceae, Ancistrocladaceae, Dioncophyllaceae, Scytopetalaceae (Scytopetalum), Medusagynaceae, Scyphostegiaceae (Scyphostegia), Sarcolaenaceae, Sphaerosepalaceae, Huaceae, Pandaceae, Crypteroniaceae, Duabangaceae, Strephonemataceae (Strephonema), Psiloxylaceae, Dirachmaceae, Phellinaceae, Lophopyxidaceae, Salvadoraceae, Medusandraceae, Mastixiaceae (Mastixia), Hoplestigmataceae (Hoplestigma) and Lowiaceae.
This flora originated on the supercontinent Gondwana, and persist in current day New Guinea, Australia, New Zealand, New Caledonia and South America.