Found is cool plant at the end of November. We are having a drought and it was growing in some thick mud at the much receded edge of a dam.
It has two types of leaves, the spear like tall ones grew while only the bottoms were submerged while I cleaned it off over a few days.
Once I put it into the tank, it grew the tall spear, it grew about 3 inches a day easily, but stopped when it broke the surface.
The blade like leaves are the ones it grows while submerged. It reproduces with runners like a val.... and the immersed version actually looks a bit like a prettier vat short val when it is small.
The pics don't do it justice. I have another much smaller one growing with only its bottom in the water outside.
I suspect it could be some sagittaria?
In case you were wondering what that was on the side
Just some crappy nearly dead plants I got from the LFS, and a topping from my dirt tank, every node except the tip has a nice root, and is growing two little new plants... I put it like this to be close to the light... (2 x 16W linear tubes over a 100L tank).