Water Caltrop

Water caltrop, Trapa natans, is a floating annual aquatic plant with edible seeds, native to warm temperate regions of Eurasia and Africa, growing in shallow freshwater and producing distinctive horned fruits. The fruits and seeds are eaten raw or boiled, and can be dried and ground into a flour called singhare ka atta, used in religious rituals and fasting observances in India and Pakistan, where the plant is known as singhara or paniphal and is widely cultivated in freshwater lakes. It has been cultivated in China and the Indian subcontinent for at least 3,000 years and is also found across the Philippines, Java, Sumatra and Japan.