Syrphid flies of many species visit blossoms to obtain nectar and pollen. Many of these syrphids, in common with other insects, also find mates at the blossoms. Males of these syrphid species make aerial patrols of inflorescences frequented by females, alternating these patrols with sitting on foliage. They pounce on or chase insects of various species and swiftly initiate copulation with conspecific females. We here present evidence that Spilomyia quadrifasciata (Say) also mate at the plants that they visit for nectar and pollen, while S. fusca Loew do not. We also indicate the seasonal occurrence of these species and list the host plants that they visit.