Immature Myzocallis carpini are pale and unmarked and have the body hairs (and a few basal antennal hairs) capitate, and very much longer than those of the adult. Winged adult M. carpini viviparae are pale yellow to yellowish white, with no dorsal abdominal markings. The forewing has a black spot at the base of the pterostigma. Their antennae are ringed with black. The body length of alate M. carpini is 1.3 to 2.2 mm.

Myzocallis coryli is similar, but only found on Hazel.

Please provide good close-up image(s) and state the host plant species.

Found on Hornbeam and may be recorded where Hornbeam occurs.

When Hornbeam is in leaf.

Widespread in Britain, but not very common.

Rarely recorded in Leicestershire and Rutland.

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