The Yellow-collared Dart (
Euxoa flavicollis) is a medium-size (30-34 mm wingspan) moth with dark brown forewings, with a pale yellow-brown, ochre, or dull orange costa. The cubital vein is shaded with white scales for the same distance. The dark filled orbicular and kidney-shaped reniform spots are relatively small and outlined in the same pale yellow or orange scales. There is a narrow yellow or orange streak beyond the claviform spot. The hindwings are suffused with sooty or brown scales, darkest towards the outer margin (Anweiler 2007).
Shropshire and Tallamy (2025) provide a list, with synonymies, of 13,055 described native, exotic, and occasional straying Lepidoptera species of North America, north of Mexico; known but undescribed taxa, taxa with unresolved taxonomy, and excluded species are also included. The
main manuscript includes links to supplementary materials, including a reference list for Lepidoptera of North America north of Mexico, and a filterable spreadsheet with information on taxonomy, synonymy, size ranges of species, distribution by state, province, and country with references, and host-plant Family and Genus associations with references.
Yellow-collared Dart adults have been collected in the province of Alberta from early July through mid August. Poorly known life history, with the immature stages known only from lab rearings. There is a single brood each year. There is apparently a relatively short period of aestivation prior to the larvae pupating. Adults are nocturnal and are attracted to light (Anweiler 2007).
In the Yellow-collared Dart, the basal half of the prothoracic collar is the same pale yellow or orange (in some females silver-grey) color as the costa, which separates it from the similar E. ridingsiana (Anweiler 2007).
Shropshire and Tallamy (2025) provide a link to a supplemental filterable spreadsheet with information on host-plant Family and Genus associations with references for all Lepidoptera species of North America, north of Mexico.