aroidgrower

Here is what I know.
The xanthosomas are really a big mess. Their is a botanist working on them and I have had him ID a lot for me. I can usually tell most common forms apart easily but their are a lot of forms that are much harder to ID and some can be possible hybrids.

Xanthosoma Atroverins Blue Giant is a form I named around 7 years ago. This is a natural form collected of Atroverins. This form grew much larger than most other forms that were used for eating. It has a dark blue leaf and does well in very hot humid summers here.

Xanthosoma Violaceum has many names it is commonly eaten and goes by the name Malanga. If you find it at exotic grocery stores as tubers.

The black boy form as well as Xanthosoma preissii Black Boy and violaceum blue giant. I believe these are all forms of Violaceum. I am not sure if they are all the exact same plant in my experience they usually are. But if you get them from a collected source at times you can get different stem colorations and larger growing forms. These may be selected varieties but with out photos as proof I dont usually buy it.

I have a few other forms I have violaceum variegated and robusta variegated as well as other forms of robusta and a very odd form that has huge leaves that cup up. Truthfully I dont know anyone that may grow more of these than I do at the moment. I hope to propagate a lot of them this season if possible.