Neuroterus tricolor is a gall wasp that has two generations per year.

The agamic gall develops on the underside of the leaf and is often cup-shaped, 2 to 4 mm in diameter, with a raised hairy rim and tufts of reddish hairs. it is attached by a short stalk.

Neuroterus albipes and Neuroterus quercusbaccarum also have disc-shaped galls on the undersides of oak leaves.

Under "Species", please select "f. agamic" or "f. sexual" as appropriate.  Provide photographs of the gall on the host plant, and note the host species.

English and Sessile Oaks.

The agamic Cupped Spangle Galls are seen in autumn.

The sexual galls develop on the underside of oak leaves in summer, often on the young leaves of "Lammas growith".  They are yellowish, flattened spheres of 2-4mm diameter, covered with red or purplish hairs when young.

Occasional in Britain but may be under-recorded.

Uncommon in Leicestershire and Rutland, but possibly under-recorded.