Exogenida Endogenida Evaginogenida Suctoria are ciliates that become sessile in their developed stage and then lose their redundant cilia.

These are supported by microtubules and phyllae, and have toxic extrusomes called haptocysts at the tip, which they attach to prey.

They then suck the prey's cytoplasm directly into a food vacuole inside the cell, where they digest and absorb its contents.

Suctoria reproduce primarily by budding, producing swarmers that lack both tentacles and stalks but have cilia.

Among the Exogenida, including common genera like Podophrya and Sphaerophrya, they appear directly on the cell surface.