Deasonia is a genus of green algae, in the family Actinochloridaceae.

[2] Deasonia is a single-celled organism.

Young cells are ellipsoidal or ovoid, while mature cells are consistently spherical with a smooth, thickened cell wall.

In young cells, the chloroplast is cup-shaped and parietal, with an off-center pyrenoid; in mature cells, the chloroplast may have bifurcations and indentations and eventually forms an irregular network, with the pyrenoid in the center.

This Chlorophyceae-related article is a stub.