Magnolia is a large genus of about 210 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae.It is named after French botanist Pierre Magnol. Magnolia is an ancient genus. Appearing before bees did, the flowers are theorized to have evolved to encourage pollination by beetles.arolus Linnaeus, who was familiar with Plumier's Genera, adopted the genus name Magnolia in 1735 in his first edition of Systema Naturae, without a description, but with a reference to Plumier's work.