M. zebra male photographed at an undisclosed location with a rare color mutation known in the aquarium trade as OB (for orange blotch) or MC (for marmalade cat). In the wild, only male mbuna (rockfish) display this mutation, with only one male out of hundreds having it. They are in great demand in the aquarium hobby and are collected unsustainably and sold by unscrupulous collectors to hobbyists in Europe, North America and Asia.