LAUSR

The flora of Papua New Guinea is amongst the richest in the world with an estimated 25,000 plant species. The extreme levels of biodiversity, climatic ranges and soil types suggest a high possibility of metal hyperaccumulator plants existing in Papua New Guinea. However, no hyperaccumulator plants have been reported from this region yet. The use of handheld X-ray fluorescence instruments is a non-destructive and effective method for the systematic quantitative assessment of hyperaccumulation in vast numbers of herbarium specimens. X-ray fluorescence scanning was undertaken at the Queensland Herbarium (Australia) on all Papua New Guinea specimens from seven major families (Celastraceae, Cunoniaceae, Phyllanthaceae, Proteaceae, Rubiaceae, Salicaceae and Violaceae), covering 3164 plant specimens. This preliminary survey revealed the existence of ten zinc hyperaccumulator species (> 3000 µg g −1 Zn), eight manganese accumulator species (> 5000 µg g −1 Mn) and one nickel hyperaccumulator species (> 1000 µg g −1 Ni). These results highlight the potential for discovery of numerous new metal hyperaccumulator plants from the flora of Papua New Guinea if larger-scale systematic screening efforts were undertaken.