Talk:Dioscorea oppositifolia

Is D. opposita valid?

According to the Missouri Botanical Garden's TROPICOS database and the USDA ARS GRIN Taxonomy database, the plant known as 'Dioscorea batatas ' is more correctly Dioscorea polystachya Turcz. This is corroborated by the Flora of China database and the Flora of North America database. The print version of the Flora of China (PDF for Dioscorea chapter available here [1]) has the following note:

The name Dioscorea opposita Thunberg (Fl. Jap. 151. 1784) has been widely used in the sense of D. polystachya, which is an earlier name for D. batatas. It was based on a misidentification of Japanese material as the strictly Indian species D. oppositifolia Linnaeus, which was cited as a synonym in the protologue, thus rendering D. opposita nomenclaturally superfluous and an illegitimate name.

Here is a link to what I believe is the correct page of the correct edition of Thunberg at Gallica (here: [2]).

GRIN Taxonomy gives a similar opinion here: [3]

I realize that D. opposita has priority, but not if it's a nomen superfluum. Any opinions from the botanists here? Chuck Entz (talk) 21:18, 21 January 2012 (UTC)

I updated this species and Dioscorea polystachya according to GRIN, Tropicos, WCSP, Flora of China, Flora of NA, Missouri Botanical Garden, ect. D. opposita is invalid - a synonym of D. oppositifolia. --MCEllis (talk) 21:43, 2 February 2016 (UTC)