winged pea Tetragonolobus purpureus, a legume native to the Mediterranean region of Europe and the Near East, is so called because its four-sided pods terminate in four ‘wings’. It is an annual, of a trailing habit, and its pods are from 3 to 9 cm (1–3") long.
The plant is cultivated in warm temperate regions, and it is sometimes grown as a culinary herb. Its flavour is acceptable, but it is hard to discern any basis for the name ‘asparagus pea’ which is sometimes used. The young pods are pickled or cooked whole. There are other plants in the genus with similar characteristics.