Members of chlorophyceae enlist about 2000 species and many preferred in aquatic habitat, both marine and fresh water. In 1935 Fritsch divided chlorophyceae into 9 orders: Volvocales, Chlorococcales, Ulotricales, Cladophorales, Chaetophorales, Oedogoniales, Conjugales, Siphonales and Charales.
Example of Chlorophyceae (Green algae)
1. Volvocales
    Examples: Chlamydomonas, Volvox, Palmella, Prasinocladus
2. Chlorococcales
    Examples: Chlorococcum, Chlorella, Westella, Pediastrum
3. Ulotricales
     Examples: Ulothrix, Ulva, Microspora, Prasiolas
4. Cladophorales
     Examples: Cladophora, Pithophora
5. Chaetophorales
      Examples: Cephaleuros, Oedocladium
6. Oedogoniales
     Examples: Oedogonium, Oedocladium
7. Conjugales
     Examples: Cylindrocystis, Spirogyra, Zygnema, Desmidium
8. Siphonales
    Examples: Protosiphon, Caulerpa, Codium
9. Charales
    Examples: Chara, Nitella