See text Pseudoblepharisma is a genus of heterotrich ciliates inhabiting oxygen depleted freshwater habitats.

It was discovered by biologist Alfred Kahl in 1926 in the Simmelried moorland near Konstanz, and was then ignored for decades.

Thiodictyon intracellulare (Chromatiaceae), a purple sulfur bacterium with a genome just half the size of their closest known relatives, and has lost genes essential for nitrogen and sulfur metabolism, and the ability to use hydrogen sulfide as an electron donor for photosynthesis.

In 2022, one strain matching these descriptions was found in tropical freshwaters of Florida, North America.

[2] The current taxonomy is inconsistent with molecular phylogeny using SSU rRNA; the latter places the genus sister to Spirostomum.