Trapa natans

Trapa natans, commonly known as the European water chestnut or water caltrop, is an aquatic plant native to Europe, Asia, and Africa. It is cultivated for its edible, nutlike fruits. The plant features submerged, feathery leaves and floating leaves arranged in a rosette. Its fruit, often called a Singhara nut, is typically 2.5 to 5 cm in diameter and has four spiny angles. Trapa natans is considered an invasive species in northeastern North America. Another species, the ling nut (T. bicornis), is grown in East Asia. The Chinese water chestnut (Eleocharis dulcis), though also called a water chestnut, belongs to a different plant family and is known for its crisp, edible corms.1