Brassica rapa
In the 18th century the turnip and the oilseed-producing variants were seen as being different species by Carl Linnaeus who named them "B. rapa" and "B. campestris". Twentieth-century taxonomists found that the plants were cross fertile and thus belonged to the same species. Since the turnip had been named first by Linnaeus, the name "Brassica rapa" was adopted.