Hi all,
Just my point of view. I have spoken to many collectors and experts in Brazil. Many agree that the purple fruiting species is the true Eugenia burkartiana. I have chosen to start using Eugenia sp. "Pitangão Amarelo da Unicamp" (I need to update our listing, I do admit) to identify the yellow fruit Helton has provided to the community.
This is directly from his website:
"INDIGENOUS NAME: PITANGA-ACEROLA (because it has a similar taste). It is also called the Yellow Pitangão of Unicamp."
Furthermore, if you refer to the botanical archives the leaves and native region of Eugenia burkartiana align with the purple fruit found by Fabio in Santa Catharina
https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:98140-2I think it is more important that the community is informed. Joe, Kam, and I imported the seeds around the same time, and at first, we all were following Helton's distinction. As Joe has stated Helton has vast knowledge and is one of the most trustworthy collectors in Brazil, but that does not mean he could be mistaken. But, science and botany are ever-evolving, and sometimes names need to be updated and the community informed (I have put this explanation in my eBay listings of Eugenia sp. "Pitangão Amarelo da Unicamp"). No one is intentionally naming species incorrectly. Both of these species are very special and should be in any serious Eugenia collection.
Another option is to distinguish based on the collectors:
Yellow fruit: Eugenia burkartiana "H. Josue"
Purple fruit: Eugenia burkartiana "F. Longen"
I hope this helps!