Identification & Distribution:
Apterae of Aphis brunellae are pale yellow, sometimes with a mid-dorsal suffusion of dark green. They are not wax powdered. In small specimens (body length less than 1.2 mm) the number of antennal segments may be reduced from 6 to 5. The abdominal dorsum is membranous with little or no sclerotic banding. The hairs on the anterior surface of the femora are shorter than the least width of the tibia. The siphunculi are dusky or dark and are 0.92 -1.90 times the length of the pale cauda. The body length of Aphis brunellae apterae is 0.98-1.45 mm.
Aphis brunellae lives up the stems or hidden among the flower bracts of self-heal (Prunella vulgaris). It is attended by ants - the colony we found had been tented over with soil particles. It does not host alternate and sexual forms appear in autumn. The self-heal aphid is rare in Britain, being previously only recorded from Buckingham and Cambridge, but now also known from East Sussex. Aphis brunellae is widespread in Europe and western Siberia.