Image acquisition
For image acquisition, diaspores were arranged on the flat scanner
avoiding any contact or overlap. The
number of sampled diaspores
varied for each taxon according to their availability in the seed
collection (Figure 3). We sampled all available material that met sample
preparation standards for up to 30 diaspores. In cases where the number
of available diaspores exceeded 30, we sampled seeds to cover an area of
up to 200 cm2. The flatbed scanner was covered with a
wooden frame 10 mm thick with a royal blue background (Figure 4). Images
were acquired with a flatbed scanner (HP Scanjet G4010) at a resolution
of 1,200 DPI to well-represent small seeds and fine appendages. All
automatic correction functions associated with the scanner software were
disabled to ensure that the RGB values of the samples were not
manipulated. The resulting images were saved in the Joint Photographic
Experts Group (JPEG) format with no compression.