Rudbeckia triloba L.

Linnaeus first descriped Rudbeckia triloba in Species Plantarum in 1753. John Torrey and Asa Gray introduced the variety pinnatiloba in 1841 in A Flora of North America: Containing Bridged Descriptions of all the known Indigenous and Naturalized plants growing North of Mexico arranged according to the Natural System. Only 3 years later, Asa Gray published Synoptical Flora of North America, including the three modern varieties, pinnatiloba, rupestris and triloba.