Canavalia rosea is a species of flowering plant of the genus Canavalia in the pea family, Fabaceae, that has a pantropical distribution. Common names include beach bean, bay bean, seaside jack-bean, coastal jack-bean, and MacKenzie bean.
Coastal jack-bean is a trailing, herbaceous vine that forms mats of foliage. Stems reach a length of more than 6 m (20 ft) and 2.5 cm (0.98 in) in thickness. Each compound leaf is made up of three leaflets 5.1-7.6 cm (2.0-3.0 in) in diameter, which will fold themselves when exposed to hot sunlight. The flowers are purplish pink and 5.1 cm (2.0 in) long. The flat pods are 10.2-15.2 cm (4.0-6.0 in) long and become prominently ridged as they mature. The buoyancy of the seeds allows them to be distributed by ocean currents. The plant seems to contain L-Betonicine.
C. rosea inhabits upper beaches, cliffs, and dunes throughout the world's coastal tropics. It is highly salt-tolerant and prefers sandy soils.