Chara

genus of green algae

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Last updated

June 24, 2026

Quick Summary

The genus Chara belongs to the order Charales, commonly known as stoneworts, which are a type of green algae. These algae are typically found submerged in freshwater environments, attached to the bottoms of lakes and rivers.12

Stoneworts superficially resemble higher plants, featuring rootlike rhizoids, branches arranged in whorls, and an erect axis. Their sexual reproduction involves a large egg within a female organ (oogonium) and sperm produced by a male organ (antheridium).1

Some Chara species are calcified, accumulating calcium carbonate deposits that can form lake marl. While generally of little direct importance to humans, stoneworts provide essential food and habitat for fish and other aquatic organisms. However, certain species can be invasive outside their native ranges.1

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algae
Annotated classification
Includes the macroscopic stonewort Chara, filamentous Spirogyra, and desmids. Class Pleurastrophyceae Freshwater and marine; includes marine flagellate Tetraselmis. Class
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Includes the macroscopic stonewort Chara, filamentous Spirogyra, and desmids. Class Pleurastrophyceae Freshwater and marine; includes marine flagellate Tetraselmis. Class
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stonewort
…(especially those of the genus Chara) and may accumulate as calcium carbonate deposits. These deposits may be so extensive that they form the major part of the calcareous marl of lakes and are sometimes a detrimental weed in fish hatcheries.
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…(especially those of the genus Chara) and may accumulate as calcium carbonate deposits. These deposits may be so extensive that they form the major part of the calcareous marl of lakes and are sometimes a detrimental weed in fish hatcheries.
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