Plant
Algae comprise several different groups of organisms which produce food by photosynthesis and thus have traditionally been included in the plant kingdom. The seaweeds range from large multicellular algae to single-celled organisms and are classified into three groups, the brown, red and green algae. There is good evidence that the brown algae evolved independently from the others, from non-photosynthetic ancestors that formed endosymbiotic relationships with red algae rather than from cyanobacteria, and they are no longer classified as plants as defined here.
Caulerpa sertularioides
The seaweed has a pale to dark-green thallus that typically grows to outward to around . It has feather-like fronds that arise from a common stolon. Each of the fronds is upright and branched. The opositely arranged branchlets are cylindrical to needle-shaped with upcurved tips with a blunt point at the end. Each branchlet has a length of and is attached to a cylindrical axis in the middle with a diameter of . Each axis connects each frond to a creeping stolon with a diameter of and a length of up to . Stolons are branched out to slim points and rhizoids then form from bottom surface these fork and penetrate the sandy substrate firmly anchoring the seaweed to the seafloor.