Halococcus morrhuae bacteria. Coloured transmis- sion electron micrograph (TEM) of a section through a group of extremophile Halococcus morrhuae bacteria. They are Gram-negative, non- motile aerobic cocci (round bacteria). They occur in highly saline environments such as salt lakes or evaporation ponds. They may also be found on the surfaces of heavily salted foods, particularly fish and meat, and can cause spoilage. Colonies of the bacteria are red in colour. Some strains can use their pigments to harness light energy when under low oxygen levels. Due to their high demand for salts, Halococcus morrhuae is not pathogenic in humans. Magnification: x12,500 at 6x6cm size.