kingdom

A new microbe called a hemimastigote was found in Nova Scotia. The Hemimastix kukwesjijk is not a plant, animal, fungus, or protozoa. It constitutes an entirely new kingdom, a new branch on the tree of life. – WTF Fun Facts

Source: https://www.scientificamerican.com/article/what-a-newfound-kingdom-means-for-the-tree-of-life/