Prasinophyceae

class of green algae

Also known as: Micromonadophyceae

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Last updated

June 30, 2026

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The Prasinophyceae, also known as Micromonadophyceae, are a group of primarily marine green algae. They are considered a paraphyletic group, meaning they do not include all descendants of their common ancestor. This class includes genera such as Micromonas, Ostreococcus, and Pyramimonas.1

Green algae, in general, are part of the division Chlorophyta and share photosynthetic pigments similar to those in higher plants. They can be single-celled, colonial, filamentous, or tubular, and reproduce both sexually and asexually. Most green algae are found in freshwater, but terrestrial and marine species also exist. The Prasinophyceae are thought to be an ancient lineage within the green algae.23

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algae
Annotated classification
Class Prasinophyceae (Micromonadophyceae) Paraphyletic, primarily marine; includes Micromonas (sometimes placed in Mamiellophyceae), Ostreococcus, and Pyramimonas. Class Ulvophyceae Primarily marine; includes Acetabularia,
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Class Prasinophyceae (Micromonadophyceae) Paraphyletic, primarily marine; includes Micromonas (sometimes placed in Mamiellophyceae), Ostreococcus, and Pyramimonas. Class Ulvophyceae Primarily marine; includes Acetabularia,
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algae
Evolution and paleontology of algae
Most consider the class Micromonadophyceae to be the most ancient group, and some fossil data support this view. The class Ulvophyceae is also ancient, whereas the classes Charophyceae and Chlorophyceae are more recent.
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Most consider the class Micromonadophyceae to be the most ancient group, and some fossil data support this view. The class Ulvophyceae is also ancient, whereas the classes Charophyceae and Chlorophyceae are more recent.
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