dinoflagellates

Dinoflagellates are tiny, one-celled organisms that live in oceans and freshwater ponds, rivers, and streams. Some dinoflagellates are like plants, depending on sunlight and basic nutrients for growth. Others are like animals, eating bacteria and microscopic organisms. They are part of a large group of diverse organisms that have been classified as "protoctists."

Image credits: main image, courtesy of Susan Carty.