12,000 species of trees in the Amazonian rainforest

Amazonia is the most biodiverse rainforest on Earth with thousands of species of animals, and tens of thousands plant species. Whereas animal numbers are well-founded, trees are understudied and their numbers contentious. In this paper, researchers compile collection data from GBIF and offline sources to provide the first exhaustive checklist of all known Amazonian trees. Their final database contains more than 500,000 tree collection records spanning almost 12,000 species belonging to 140 families and 1225 genera. The average collection density found is only 10 per 100 km2, and while some areas surrounding cities, such as Manaus, has almost 25,000 records, other remote areas totalling 320,000 km2 are void of collections. The researchers find only a weak effect of population size of species on the number of collections, whereas the effect of range size was more pronounced. The paper concludes by recommending increased data exchange, curation, and digitization rather than focusing on collecting more specimens.