Sold as a single plant with growing leaves (not just a bulb) 
Aponogeton ulvaceus is a bulb species in the aponogeton family and originates in Madagascar.
The leaves are delicate light-green and transparent.  A single bulb can produce more than 40 leaves, 10-24 inches long, and a plant total width of up to 20 inches. This plant is best as a main centerpiece plant in larger aquariums. It is relatively tolerant, and thrives in both soft and hard water. Grows best under medium lighting.