. . . . . . . . . "Eristalis tenax" . . "Arctotheca calendula" . . "Jon Sullivan. 2017. Eristalis tenax interaction->visited flower of Arctotheca calendula. iNaturalist.org. Accessed at <https://www.inaturalist.org/observations/8166471> on 05 Apr 2018." . . . . "http://iNaturalist.org is a place where you can record what you see in nature, meet other nature lovers, and learn about the natural world." .