Short mine leading from the midrib to the petiole, where a gall is formed.

According to Erik van Nieukerken, the larva of this species seems to behave similarly to that of Ectoedemia populella but forms a less conspicuous gall.
Hosts: P. balsamifera, P. trichocarpa.
Distribution: BC, AB, ON, QC, NS, CA.
References: Wilkinson & Newton (1981); Pohl et al. (2018).