This plant is currently placed in a monogeneric family Penthoraceae, with just two species worldwide, the other one in Asia and European Russia. It was previously included in Saxifragaceae. It is called "stonecrop" as it visually resembles true stonecrop (Sedum) in its flowers and star-shaped seed capsules and thus was once placed in Crassulaceae. Its specific epithet sedoides also means "resembling sedum."