The Chroococcales (/ˌkroʊəˌkɒˈkeɪliːz/[2]) are an order of cyanobacteria in some classifications which includes the harmful algal bloom Microcystis aeruginosa.

[3] Molecular data indicate that Chroococcales may be polyphyletic, meaning its members may not all belong to the same clade or have the same common ancestor.

[1] The order is characterized by single, floating cells or colonies which are embedded to a matrix.

Also, a lack of differentiation between apical and basal structures exists.

This Cyanobacteria-related article is a stub.