Figure 21.3: “Green Algae” Consist of Several Distantly Related Groups (A) Sea lettuce, a chlorophyte, grows in ocean tidewaters. (B) The coleochaetophytes are thought to be the sister group of stoneworts plus land plants. (C) The land plants probably evolved from a common ancestor shared with stoneworts, which display the branching pattern we otherwise associate with land plants. A stonewort in the common freshwater genus Chara is shown here. The orange structures are male sex organs.