New Guinea is the planet’s most floristically diverse island, reports a comprehensive assessment of vascular plant species published in the journal Nature.
The species list, which was compiled by 99 botanists from 56 institutions across 19 countries, verified the identity of over 23,000 plant names from over 704,000 specimens collected from New Guinea since the 1750s.

The research concludes New Guinea has 13,634 species of plants from 1742 genera and 264 families. That gives New Guinea, the world’s second largest island, the highest plant diversity of any island on Earth, surpassing Madagascar (11,832 species), Borneo (11,165 species), and Sumatra (8,391 species). New Guinea’s diversity of plants is greater than that of the entire archipelago of the Philippines (9,432 species).
Just five families account for more than a third of plant species on the island. Orchids, with 2,856 species or 21% of the island’s species, are the most diverse.
There are 3,962 species of trees in New Guinea or about four times the number found across all of North America.