Capsella is a genus of herbaceous annual and biennial plants in the family Brassicaceae.

[3] Capsella rubella is a self-fertilizing species that became self-compatible 50,000 to 100,000 years ago.

In general, the shift from outcrossing to self-fertilization is among the most common transitions in flowering plants.

Capsella rubella is studied as a model for understanding the evolution of self-fertilization.

[4][5] The name is said to derive from Latin capsa, a box or case, alluding to fruit resembling a medieval wallet or purse;[6] the suffix -ella denotes "lesser".