Dianthera pectoralis is an herb in the family Acanthaceae. This water-willow is widely known as tilo in Latin America and in Cuba. In Haiti, it is called chapantye and zeb chapantyè on Dominica and Martinique. Other folk names are freshcut, chambá carpintero ("carpenter"), té criollo ("Criollo tea"), curia, death-angel, masha-hari, or "piri piri". This species was described by Nikolaus Joseph von Jacquin in 1760, who provided additional data in 1763. A well-marked variety, var. stenophylla, was described by Emery Clarence Leonard in 1958.