(Figs. 2, 63)
Material examined. VERMONT: Chittenden Co., South Burlington, Winooski Gorge, 29.vi.2014, em. 20.vii.2014, C.S. Eiseman, ex Populus balsamifera, #CSE1203, CNC384877, CNC384878 (1♂ 1♀).
Hosts. Salicaceae: Populus balsamifera L., P. tremuloides Michx, P. trichocarpa Torr. & A. Gray ex. Hook. (Spencer 1969); recorded from various other Populus and Salix species in Europe (Ellis 2016).
Leaf mine. (Fig. 63) A “large greenish blotch mine, which turns brown with age” (Spencer 1969). The mine that was photographed at the time of collection was a gradually expanding blotch along the leaf margin, with four larvae advancing together side by side. The newest portion was greenish and the rest was turning brownish. Frass was in small, scattered, irregular particles.
Puparium. (Fig. 2) Reddish-brown, 2.3 mm by 1.3 mm; formed outside the mine.
Distribution. * USA: VT; Canada: BC; Europe.
Comments. See comments under Agromyza isolata.