Definition for Rehmannia
From Biology Forums Dictionary
Rehmannia is a genus of six species of flowering plants in the order Lamiales, endemic to China. The genus was included in the family Scrophulariaceae or Gesneriaceae in some older classifications. The current placement of the genus is in neither Scrophulariaceae s.s. nor Plantaginaceae s.l. (to which many other former Scrophulariaceae have been transferred). Earlier molecular studies suggested that its closest relatives were the genera Lancea and Mazus, which have been included in Phrymaceae. Subsequently it was found that Rehmannia and Triaenophora are jointly the sister group to Lindenbergia and the parasitic Orobanchaceae.