Donate Take Action

Join us


Marine Animal Encyclopedia

Halosphaera viridis Acetabularia acetabulum

Halosphaera viridis is a small, pear-shaped cell with four swimming flagellae at one end. It reproduces by splitting in two, allowing it to reach high concentrations and from time to time some cells become small cysts whose contents divide into small disks. Each disk eventually becomes a flagellated Halosphaera viridis cell that will be released into the sea. There can be hundreds of cysts per square yard in the open ocean, and they are probably a vital food source for larger zooplankton.

Halosphaera viridis habitat mapzoom image
  • Class Prasinophyceae
  • Size 20–30 micrometers (motile phase)
  • Distribution Northeastern Atlantic, eastern Pacific