Ismene, or Peruvian daffodil, is a genus of South American plants in the Amaryllis family.

[6] The species are native to Peru and Ecuador and widely cultivated elsewhere as ornamentals because of their large, showy flowers.

However, its morphology differs from Hymenocallis in several significant ways: its vegetative parts, natural range, and chromosome number are all distinct.

[5] It is closely related to Leptochiton and Hymenocallis, from which it separated 26.14 million years ago.

The separation of Leptochiton and Hymenocallis occurred 24.46 million years ago.