The wingspan is 8–9 mm. The head is dull ferruginous, mixed with fuscous in middle. Antennal eyecaps white. Forewings are dark fuscous; two whitish costal spots before middle and at 3/4, and two on dorsum somewhat anterior to these; cilia ochreous-tinged. Hindwings are grey. The larva is yellowish -green, anteriorly reddish-tinged; dorsal line darker; dots whitish. The head is pale brown.[2][3]
Adults are on wing May to June. At times there is a second generation in August.The larvae create a gallery mine in the leaves of alder, including common alder (Alnus glutinosa), grey alder (Alnus incana), green alder (Alnus viridis) or myrtle (Myrica gale).
^Meyrick, E., 1895 A Handbook of British Lepidoptera MacMillan, London pdf This article incorporates text from this source, which is in the public domain. Keys and description
^ Zagulajev, A.K., 1990 Bucculatricidae ; in G.S. Medvedev (ed.): Keys to the insects of the europaean part of the USSR, Vol.IV: Lepidoptera, part 2 (english translation), Oxonian Press Pvt.Ltd., New Dehli, 1987