I don't know if GRIN is more up to date on names, if you click on the species it gives the last update. The problem is with 'authorities', there's more than one authority and they often differ in 'opinion'!
http://www.ars-grin.gov/cgi-bi...
GRIN has both accepted, where The Plant List gives var. aphrodisiaca as a synonym, date supplied April 2012 which is more up to date than GRIN.
http://www.theplantlist.org/tp...
The Plant List:
Collaboration between the Royal Botanic Gardens, Kew and Missouri Botanical Garden enabled the creation of The Plant List by combining multiple checklist datasets held by these institutions and other collaborators.
http://www.theplantlist.org/1....
There's been a lot of shaking up of names in the last few years, researchers can now us DNA to check where a plant belongs, or what it really is. Often a plant name is being reverted to the first given name as first in time takes priority, it's not only happening in the plant world but also in the insect world.
I assume the link you gave isn't the seller of your seeds as it doesn't mention the location. Can you post a link to the seller's site?
Another search idea is to search for the 'flora of Suriname', a quick look shows lot of sources but not much info.
I found "The Medicinal Plant Trade in Suriname" but a page search didn't bring up Turnera, Common names might get results.
http://lib-ojs3.lib.sfu.ca:811...
Interesting! "A HISTORICAL COLLECTION OF USEFUL PLANTS FROM SURINAME (CA. 1689)."
Under Conclusion:
The Surinam Hermann herbarium is of great importance to the flora and ethnobotany of Surinam. It is the oldest documentation of local names and uses accompanied by actual vouchers from Surinam and contains the first physical evidence of African crops introduced to Surinam.
http://www.hermann-herbarium.n...
Lots of resources which might be useful ..
http://botany.si.edu/bdg/medic...
