Very common resident.

Larva feeding on Alders Alnus glutinosa and A. cordata in two generations in July and again in September and October. Forms a gallery usually with linear frass, but sometimes dispersed, though vacated mines cannot be reliably distinguished from those of S. glutinosae.

Larva a paler yellow than that of S. glutinosae, mining dorsum upwards and without the ventral prothoracic plate of that species (which mines venter upwards). Caution is advised, however, and rearing through to adult is recommended.

Verification Grade Comment: Examination of larva essential

	Mine: Either the leaf or a good photograph required

Recorded in 35 (25%) of 140 10k Squares.
First Recorded in 1874.
Last Recorded in 2020.
(Data up to end 2022)