. . . . . . . . . "Danaus plexippus" . . "Calendula officinalis" . . "KT Thalin. 2017. Danaus plexippus nectar plant Calendula officinalis. iNaturalist.org. Accessed at <https://www.inaturalist.org/observations/8420920> 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." .