Androconial spot of the hind wing of the african butterfly Bicyclus anynana. Androconial scales are scales of lepidoptera that are specialized for the dispersion/production of sexual pheromones. The term is generally used for male only (but some authors seems to use it also for females). The yellow hairs that cross the picture are part of a hair pencil that has been removed for the picture. This hair pencil also play a role in the dispersion of the sexual scent.
scale : image width = 1.7 mm

Technical settings :
– focus stack of 60 images
– microscope objective (Nikon achromatic 10x 160/0.25) on bellow