Found predominantly in freshwater, Actinophyrs sol is common in lakes, ponds, and pools. The species usually reproduces via binary fission, but can also propagate through autogamy, which results in zygotes that are able to defer development until conditions are suitable. A similar species, Acanthocystis turfacea, colored by the green algae with which it lives in symbiosis, is frequently called the green sun animalcule.