Seaweed
"Seaweed" is a colloquial term and lacks a formal definition. A seaweed may belong to one of several groups of multicellular algae: the red algae, green algae, and brown algae. As these three groups do not have a common multicellular ancestor, the seaweed are in a polyphyletic group. In addition, some tuft-forming bluegreen algae (Cyanobacteria) are sometimes considered to be seaweed.
Caulerpa sedoides
The light to medium green delicate alga or seaweed with a [thallus]] that grows to a size of around . It has small elongated ovoid shaped beads arranged loosely along the main stolon or axis. The stolon is often branched and arises from rhizomes or running stolons) that are usually fixed to rocky surfaces in a marine environment.