The larvae of the gall midge Acericecis campestre gall the leaves of various members of the family Sapindaceae which include Maples and Sycamore. A single larva lives in a small depression at the underside of the leaf.  The upper side has a corresponding small bulge, less than 1mm highwhich is surrounded by a pale yellowish circle. After the larva has vacated the gall, a yellow spot remains then eventually withers. The larva is whitish, almost hyaline, short and squat. 

Gall Adult

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The galls may be found where the host plants occur.

The galls may be seen when the host species are in leaf.

Univoltine, pupation in the soil.

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

Status in Leicestershire and Rutland not known.