It is commonly believed that bacteria are microscopic – stealthy and hidden from the naked eye. But the bacterium, Epulopiscium fishelsoni, is a microbial behemoth you can see with the human eye alone. First discovered in the intestines of a brown surgeonfish in the Red Sea in 1985, this giant bacterium was first classified as a protist because of its large size. In 1993, rRNA sequencing revealed that this organism is actually a bacterium.
Epulopiscium varies between 10- to 20-fold in length and has a volume more than 2,000 times that of a typical bacterium. They range from 200 - 700 microns in length, about the size of a grain of table salt. But being big does have its downsides. (more…)