During the summer of 1926, while collecting in Orillia, numerous small flies were observed on old fence posts in the hot sun. It was presumed that they represented some common species of Agromyzinae and only six specimens were captured after much difficulty, four of these proving to belong to a beautiful undescribed species of Mallochiella. In Melander's key to the Milichiinae (Jour. N. Y. Ent. Soc., XXXI, 1913) the members of this genus trace to Hypaspistomyia Hendel, an Asiatic genus, but the oral margin is not retracted. The carinate lunule is variable both in size and color in M. halteralis Coq. but always separates the antennae.