Nothing is available online.
Your among the first dozen or so people to have ever grown it for aquarium usage. I first got it as a gift from a hobbyist in Brazil, who gave it to me emersed. They had not tried it in submersed culture when I gave it to them. They actually thought it was a Rotala species, but I eventually figured out that it was actually an aquatic Hedyotis -- don't know the species yet.
I found it extremely easy to grow and actually a little obnoxious, as it has a tendency to shed growing tips which settle elsewhere in the aquarium and grow new plants. Seems to like CO2 and lots of traces/PO4.
There is actually another plant I gave to Jim that is a Rotala, but from the same place the Hedyotis was collected. This one has bright red stems emersed. Submersed, it looks identical to Rotala "Green" save for its tendency to carpet the substrate -- it seems to be a new foreground option.
Have fun with it,
Carlos