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 uncertain; it belongs to neither Scrophulariaceae s.s. nor Plantaginaceae s.l. (to which many other former Scrophulariaceae have been transferred), nor does it seem to belong with any of the other major clades of Lamiales. Molecular studies suggest that its closest relatives are the genera Lancea and Mazus (Oxelman et al., 2005), which have been included in Phrymaceae (Beardsley & Olmstead, 2002).

Sometimes known as Chinese Foxglove due to its superficial resemblance to the genus Digitalis, the species of Rehmannia are perennial herbs. The plants have large flowers and are grown as ornamental garden plants in Europe and North America, and are used medicinally in Asia. Known as dìhuáng (地黄) in Chinese, R. glutinosa is used as a medicinal herb for a variety of ailments such as anemia, dizziness and constipation. Rehmannia contains the vitamins A, B, C, and D, as well as other useful compounds.

Selected species

• Rehmannia chingii
• Rehmannia elata
• Rehmannia glutinosa
• Rehmannia henryi
• Rehmannia piasezkii
• Rehmannia solanifolia

References

• Oxelman, B.; Kornhall, P.; Olmstead, R.G.; Bremer, B. 2005. Further disintegration of the Scrophulariaceae. Taxon 54 (2): 411-425.
• Beardsley, P. M. & Olmstead, R. G. 2002. Redefining Phrymaceae: the placement of Mimulus, tribe Mimuleae, and Phryma. American Journal of Botany 89: 1093-1102 (available online).
• Flora of China: Rehmannia

Scrophulariaceae | Lamiales | Traditional Chinese medicine | Dietary supplements | Medicinal herbs and fungi