Stentor

Stentor, previously known as trumpet animalcules, is a genus of trumpet-shaped, ciliated protists common to most of the world. Members share a wide anterior feeding end and a tapered posterior tail end where they commonly adhere to a substrate, and are very large cells, ranging from roughly 0.4 to 2 millimetres depending on species, with fine control over their bodies that lets them contract into a small ball or extend and widen their feeding end. They feed heterotrophically, using cilia to draw prey into a large oral opening, and many species carry endosymbiotic algae that supply additional nutrients from sunlight. Stentor are also known for remarkable regenerative ability, since even a small fragment of the cell can regrow into a whole organism.