In this species all adult forms are winged, and range in size from 3.2 to 4.3 mm long. They have red eyes, a brown thorax, and a pale green abdomen. The upper surface of the abdomen has up to 5 or 6 variably developed dark cross-bars. Early in the year these cross bars may be reduced or absent altogether. The two tubes (siphunculi) at the rear end are pale, long and thick. Nymphs lack wings and are all green.

This aphid spends all year on Sycamore but has also been recorded from many other Acer spp., but these are apparently only visited on a casual basis.

Late spring to late autumn

This species overwinters as eggs placed in bark crevices and behind buds. The eggs hatch in early spring, and there is a migration in late spring/early summer.

Common and widespread in Britain though poorly recorded.

Common in Leicestershire and Rutland.

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