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Important Plant Areas of New Guinea

Number of IPAs: there is no full Flora of the New Guinea ecoregion at present

New Guinea covers 2,500 km from west to east

Ground level rainforest

New Guinea is the largest tropical island in the world. Lying just below the equator, it spans about 2,500 km from west to east. There is no full Flora of the New Guinea ecoregion, however there is a recent checklist of the vascular plant species (Cámara-Leret et al. 2020). New Guinea is also relatively under-collected, with fewer than 25 collections per 100 km2 throughout the mainland, with fewer records in Indonesian New Guinea compared to Papua New Guinea.


Its complex topography, with mountains up to 4,884 m elevation, and diverse range of ecosystems, from mangroves to alpine vegetation, support a vast amount of plant diversity, with at least 9,300 species (68%) endemic to the island.


New Guinea is one of the last places in South-east Asia with large areas of continuous forest. However, this is under threat from mining, palm oil concessions, timber extraction and infrastructure development. There is an urgent need to understand how New Guinea’s plant diversity is distributed across the island, how it evolved, what threats there are, and how it will cope with land use change and predicted climate change to inform focused and coordinated conservation actions.

Tropical Important Plant Areas (TIPAs) Project

The present Tropical Important Plant Areas (TIPAs) project (2022 to 2024) is focussed on the Indonesian province of West Papua and is a partnership between Royal Botanic Gardens Kew, Universitas Papua (UNIPA) and Dinas Kehutanan West Papua. The project partners are building a georeferenced specimen dataset of the endemic species of West Papua to help predict species occurrence in different habitat types. Future fieldwork will test how well the models predict species occurrences and richness.

A list of the threatened and range-restricted plant species is currently being refined by the project partners. Kew and collaborators have recently assessed and published 226 New Guinea orchid and tree fern species on the IUCN Red List: 27 species (11.5%) are threatened with extinction and 44 species (18%) were listed as Data Deficient. Future assessments are focused on the endemic woody plants of West Papua.


Trees of New Guinea

Research Paper

Cámara-Leret, R., Frodin, D.G., Adema, F. et al. New Guinea has the world’s richest island flora. Nature 584, 579–583 (2020).

Tropical Important Plant Areas (TIPAs) in Indonesian New Guinea