Epulonipiscium

Epulonipiscium, formally Candidatus Epulopiscium, is a genus of Gram-positive bacteria that live in a symbiotic relationship with surgeonfish. The bacteria are known for their unusually large size, with many individuals ranging from 0.2 to 0.7 millimeters in length. Before the 1999 discovery of Thiomargarita namibiensis, Epulonipiscium species were considered the largest known bacteria, and they remain the largest known heterotrophic bacteria. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/