Sample preparation
We cleaned the diaspores with the aid of a stereo microscope and only selected diaspores with all structures in a well-preserved state, apart from three exceptions. 1) Fleshy covering structures and some fleshy outgrowths were removed due to the pronounced changes that these structures undergo after dispersal, which can lead to unrecognisable colours, shapes, and sizes. 2) We measured diaspores without scales or covering structures when most diaspores in a vial of the seed collection had detached from these structures without handling. 3) Hairy appendages (e.g., pappus and plumes) were removed due to requirements of the method (details in Dayrell et al. 2023). The structures that were not present in the scanned diaspores were recorded as ‘missing structures’ in the dataset.