Chlorophytes
Chlorophyta
The chlorophytes includes a lineage of about 4,000 species of aquatic green algae. They are a sister group to the land plants, and their green algae relatives. The chlorophytes have unicellular, colonial, and multicellular representatives. Most are free-living in water, but some form symbioses with lichens, and can survive as terrestrial algae.
Diversity
The chlorophytes are represented by approximately 11 families:
Chlorodendrophyceae
Chloropicophyceae
Mamiellophyceae
Nephrophyceae
Palmophyllophyceae
Pedinophyceae
Picocystophyceae
Pyramimonadophyceae
Trebouxiophyceae
Ulvophyceae
Chlorophyceae
These last two group are covered below and in class.
Right: Gulbrandsen et al. 2021, Figure 1
Chlorophyceae
e.g. Chlamydomonas, Volvox, Pediastrum
Live in mostly freshwater or terrestrial algae
Unicells, colonies, some filaments in this group
Produce a phycoplast during cell division; a structure that forms parallel to cytokinesis
Above: the colonial chlorophycean algae, Volvox, which grows as a colonial organism
Ulvophyceae
e.g. Ulva, Codium, Aegagropila, Derbesia, Chaetomorpha, etc.
Live in mostly marine habits
Siphonous and thalloid growth
During telophase (mitosis), they go through furrowing cell division
Above: an ulvophycean alga, Codium
Above: the chlorophycean alga Chlamydomonas
Above: "moss balls" or marimo are clusters of the filamentous ulvophyte, Aegagropila
Additional Resources
Unraveling Caulerpa’s Growth Mysteries: Insights Into A Single-Cell Algae’s Development (Science Blog 24Nov2023)
Algae injected into animals produce oxygen in the brain (Ozugur et al. 2021)
Single-Celled Algae Evolve Into a Multicellular Organism (Science Alert, 23 Feb 2019)