Ronald Good in the context of "Natural History Museum, London"

Antarctic flora are a distinct community of vascular plants which evolved millions of years ago on the supercontinent of Gondwana. In 2025, species of Antarctica flora reside on several now separated areas of the Southern Hemisphere, including southern South America, southernmost Africa, New Zealand, Australia, and New Caledonia. Joseph Dalton Hooker (1817 – 1911) was the first to notice similarities in the flora and speculated that Antarctica had served as either a source or a transitional point, and that land masses now separated might formerly have been adjacent.

Based on the similarities in their flora, botanist Ronald D'Oyley Good identified a separate Antarctic Floristic Kingdom that included southern South America, New Zealand, and some southern island groups. In addition, Australia was determined to be its own floristic kingdom because of the influx of tropical Eurasian flora that had mostly supplanted the Antarctic flora and included New Guinea and New Caledonia in the Paleotropical floristic kingdom.

The Paleotropical kingdom (Paleotropis) is a floristic kingdom composed of the tropical areas of Africa, Asia and Oceania (excluding Australia and New Zealand), as proposed by Ronald Good and Armen Takhtajan. 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. Flora from the Paleotropical kingdom influenced the tropical flora of the Australian Kingdom. The kingdom is subdivided into five floristic subkingdoms according to Takhtajan (or three, according to Good) and about 13 floristic regions. In this article the floristic subkingdoms and regions are given as delineated by Takhtajan.