Caltha palustris
The oldest description that is generally acknowledged in the botanical literature dates from 1700 under the name "Populago" by Joseph Pitton de Tournefort in part 1 of his Institutiones rei herbariae. He distinguished between "P. flore major", "P. flore minor" and "P. flore plena", and already says all of these are synonymous to "Caltha palustris", without mentioning any previous author. As a plant name published before 1 May 1753, "Populago" is invalid. And so is the first description as "Caltha palustris" by Carl Linnaeus in his Genera Plantarum of 1737. But Linnaeus re-describes the species under the same name in Species Plantarum of 1 May 1753, thus providing the correct name.