my stems have long spear shaped leaves at the top and round ones towards the bottom. ok here is more evidence that Rotala indica is ALSO Rotala rotundifolia. note the last sentence of the paragraph! i was under the impression that tropica.com is a very reputable site, no?
Well from what the site said that the marsh variety has round leaves and the aquaria variety doesnt. It may just be the same plant. They change scientific names so many times who knows anymore. Even the PD here says Rotala rotundifolia, Rotala indica.