Antenna cleaner of C. rufifemur ants. (a) Scanning electron micrograph of the antenna clamped by the cleaner (view from the outer=posterior side). (b) Tarsal notch. (c) Tibial spur. Images in (b,c) are coloured to show the bristles (red), the comb (blue) and the brush (green). Scale bars, (a) 150 μm, (b) 100 μm and (c) 50 μm.
Location of particles of different size on the tarsal notch after a single cleaning stroke, given for each particle size as the percentage found on bristles, comb and brush. For each particle size, n=7 cleaning structures of different ants.
Schematic diagram summarizing how cleaning hairs on the ant's antenna cleaner may act as a sequential particle filter: (i) the bristles are responsible for picking up the largest particles from the antennae; (ii) the comb removes particles smaller than the gaps between the bristles but larger than the gaps of the comb; (iii) even smaller particles adhere to the flexible setae of the brush.