Macrosiphoniella artemisiae apterae are greyish-green and wax powdered. The antennae and legs are mostly black, except for the base of antennal segment III and the basal part of the front femur which are brown. The siphunculi and cauda are entirely black. The body length of Macrosiphoniella artemisiae apterae is 2.3 to 3.6 mm.

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Where Mugwort occurs.

Mugwort flowers in July to September in Europe, so populations of Macrosiphoniella artemisiae usually peak around this time. It is commonly found on the flower heads with other species of aphids in mixed species populations.

The Mugwort Aphid lives on the upper parts of Mugwort (Artemisia vulgaris) especially amongst the flowers. Sexual forms occur in the autumn, and the species overwinters as eggs.

True status in Britain is difficult to determine due to lack of records.

Status in Leicestershire and Rutland not known.

https://influentialpoints.com/Gallery/Macrosiphoniella_artemisiae_mugwort_aphid.htm