The species are floating annual aquatic plants, growing in slow-moving water up to 5 m deep, native to warm temperate parts of Eurasia and Africa. They bear ornately shaped fruits, which in the case of "T. bicornis" resemble the head of a bull or the silhouette of a flying bat. Each fruit contains a single very large, starchy seed. "T. natans" and "T. bicornis" have been cultivated in China and the Indian subcontinent for the edible seeds for at least 3,000 years.