Chamaecrista nictitans

Chamaecrista nictitans, the sensitive cassia, sensitive partridge pea, small partridge pea or wild sensitive plant, is a herbaceous species of legume widely distributed through the temperate and tropical Americas. It is an annual plant capable of rapid plant movement—its leaflets fold together when touched. However, a population at Haleakala National Park on the island of Maui, Hawaii, was reported as not being sensitive to touch.