Perennial suffruticose herbs or scrambling shrubs. Leaves opposite, entire, often sinuate-repand. Flowers bisexual. Involucral bracts present. Perianth 5-lobed, campanulate or infundibuliform. Stamens 2-5; filaments unequal, connate at the base. Style filiform, stigma peltate. Anthocarp clavate, 10-ribbed, viscid and glandular with large wart-like glands.