Arcanobacterium haemolyticum. Coloured transmission electron micrograph (TEM) of the Gram- positive bacterium Arcanobacterium haemolyticum, formerly known as Corynebacterium haemolyticum. It grows in culture as irregularly- shaped rods, as seen here. This organism is an indigenous part of the natural pharyngeal and skin flora, but it may become pathogenic causing skin infections and pharyngitis. Magnification: x26, 400 at 6x4. 5cm size.