Unravelling the ill-conceived Magnolia lacei synonymy complex reveals the negative consequences of unsubstantiated synonymy to Magnoliaceae species

Due to the now almost universal recognition that the family Magnoliaceae includes two subfamilies, Liriodendroideae and Magnolioideae, with each subfamily consisting of one genus, a new name is proposed and three new combinations are formally made to transfer four additional species from Michelia to Magnolia, the remaining genus in Magnolioideae. The following four species Michelia magnifica, M. pachycarpa, M. tignifera and M. uniflora have been treated as heterotypic synonyms of Michelia lacei since 1993, but are now restored because, based on extensive comparative data, the authors have determined that they are the unique species originally described and named by their respective authors.

The necessary replacement name Magnolia magnificentia is proposed for Michelia magnifica which would otherwise produce an illegitimate later homonym to an existing fossil name in Magnolia. The remaining three taxa retain their specific epithets when transferred as new combinations to Magnolia. Finally, some notes and recommendations on the in situ and ex situ conservation of each of these four synonymised species are presented.

These four species have apparently rarely, if ever, been independently evaluated in the wild, because more than 30 years ago they were reduced to unsubstantiated synonyms of the probable Myanmar endemic Michelia lacei.