A common but local species in Belgium.

The larva makes a leafmine usually starting close to  a rib of mainly Crataegus, but also found on other plants like Cotoneaster, Cydonia, Amelanchier, Malus, Prunus avium, Pyrus and Sorbus aucuparia. It pupates in a dark brown cocoon, generally spun on the surface of the soil.

The adults fly in mainly in June. 

ID mine: starts as a long, slender gallery with linear frass, often following a rib or leaf margin and sometimes going down petiole before turning back into the blade of the leaf. Eventually, the gallery becomes wider with reddish frass in neat arches. 
Mine long, not forming a blotch, but often makin hairpin bends and often extending right across the leaf.