Taxonomy
In the system of Adl et al. 2005, the red algae are classified in the Archaeplastida, along with the glaucophytes and green algae plus land plants (Viridiplantae or Chloroplastida). The authors use a hierarchical arrangement where the clade names do not signify rank; the class name Rhodophyceae is used for the red algae. No subdivisions are given; the authors say, "Traditional subgroups are artiļ¬cial constructs, and no longer valid."
The system reflected the consensus in 2005. Many studies published since then have provided evidence which is in agreement. However, other studies have suggested Archaeplastida is paraphyletic. As of January 2011, the situation appears unresolved.
Below are other published taxonomies of the red algae, although none necessarily has to be used, as the taxonomy of the algae is still in a state of flux (with classification above the level of order having received little scientific attention for most of the 20th century).
- If one defines the kingdom Plantae to mean the Archaeplastida, the red algae will be part of that kingdom
- If Plantae are defined more narrowly, to be the Viridiplantae, then the red algae might be considered their own kingdom, or part of the kingdom Protista.
A major research initiative to reconstruct the Red Algal Tree of Life (RedToL) using phylogenetic and genomic approaches is funded by the National Science Foundation as part of the Assembling the Tree of Life Program.
Read more about this topic: Red Algae