Thiomargarita namibiensis

Thiomargarita namibiensis is a bacterium that was first described in 1999; it is the only known member of its genus. It is a sulphur bacterium found on the continental shelf off the coast of Namibia. What makes this species so remarkable is that it is the largest bacterium ever discovered. With a diameter of 0.3mm, it can be seen with the naked eye.