. . . . . . . . . "Danaus gilippus" . . "Centaurea americana" . . "anthonyh. 2016. Danaus gilippus nectar plant Centaurea americana. iNaturalist.org. Accessed at <https://www.inaturalist.org/observations/3351779> 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." .