Sibthorpia europaea is a species of flowering plant known by the common name Cornish moneywort.

The genus Sibthorpia is named after Dr Humphry Sibthorp who was the Sherardian Professor of Botany at the University of Oxford from 1747 to 1783.

[2] Sibthorpia europaea is a small prostrate plant forming mats of thread-like stems which root as they creep across the ground.

[4] It typically inhabits moist, shady locations such as stream-banks, the sides of ditches, woodland, wet heathland, shady path verges, lawns and old walls and banks with a thin covering of soil.

In Ireland it grows at altitudes up to 515 m (1,690 ft) but populations seem to be dwindling as it faces competition from the more aggressive New Zealand willowherb.