土丁桂属（学名：Evolvulus）是旋花科下的一个属，为草本、亚灌木或灌木植物。该属共有约100种，主要分布于美洲热带。

Evolvulus is a genus of flowering plants in the Convolvulaceae, the morning glory family. They are known generally as dwarf morning glories. Most all are native to the Americas. There are about 100 species.