ABOVE: The ciliate Pseudoblepharisma tenue harbors both green algae and purple bacteria as symbionts.
SEBASTIAN HESS
More than a century ago, a German schoolteacher named Alfred Kahl made a career change, becoming a student of protozoologist Eduard Reichenow. In 1926, when he was almost 50, Kahl published a paper in which he identified, classified, and described hundreds of new species of protists. One of those, Pseudoblepharisma tenue, is a ciliate found in the Simmelried moorland, about eight acres of wetlands in southern Germany. In his manuscript, Kahl remarked upon rose-colored bacteria and green algae living within the body of P. tenue, but no one ever followed up on that peculiar observation, until now.
In a study published June 11 in Science Advances, researchers confirm that P. tenue has two types of symbionts—a green alga and a purple bacterium—an unusual feature in a eukaryote.
“Normally, symbionts are a more specialized component, and ...
