Westella is a genus of green algae in the family Oocystaceae.

It is found in freshwater habitats such as ponds and lakes, as part of the phytoplankton.

[2] Willea consists of four-celled (rarely two-celled) colonies (termed coenobia); the coenobia may be aggregated to form compound colonies of 100 cells or more, arranged in a single plane.

The cells are oval to cylindrical, arranged in a rectangle forming a rhomboidal gap.

[1] Asexual reproduction occurs by the formation of autospores, which are organized into coenobia; they enlarge with the cell wall, which eventually dissolves, releasing the new cells.