Twining herb to 3m, reddish stems with white to pale purplish hairs. Leaves to 80mm x 56mm, purplish beneath with doubly serrate margins. Up to 20-f;owered cymes with bracts to 40mm x 22mm, light green sepals oftern suffused purple, to 12,mm x 8,4mm, light yellow to sulphur-yellow corolla, upper lip 7mm x 9mm, lower lip 23mm x 15mm. Villous capsule 7mm long.