The brown arborvitae leafminer or brown cedar leafminer (Coleotechnites thujaella) is a moth of the Gelechiidae family. It is found in the north-eastern parts of the United States, as well as Canada. The wingspan is 9–10 mm. The forewings are cream white with three outwardly oblique, roughly triangular, black costal patches, all edged outwardly with whitish scales. The inner begins at the base and extends nearly to the dorsum, the middle patch at the inner third and the outer at the outer third are both smaller and reach only to the median line. There is a denser cluster of black raised scales at the lower apex of each forming a distinct black dot. Below each, close to the dorsum is a small black dot and close to the costa between the basal and middle patch is a sixth black dot, these six