(Gyrostemon subnudus)
Seeds of four species of South American Agalinis, five species of Aureolaria, the monotypic Brachystigma, and two species of Tomanthera were examined with the light microscope and the scanning electron microscope. The outer cells of seed coats form a reticulum in all taxa. The surfaces of radial walls of seed coat cells are striate, papillate, tuberculate, or granular. The inner tangential walls of seed coat cells may be smooth or a pattern of thickenings may be formed on them. Seed morphology is distinctive for each species of Agalinis, Brachystigma, and Tomanthera. Within Aureolaria the seeds are very similar among those taxa with winged seeds. The wingless, smaller seeds of Aureolaria pedicularia are distinctive.