Phractolaemus ansorgii is a freshwater fish native to tropical West and Central Africa and is the sole species of the genus Phractolaemus. One of its most remarkable features is its small mouth, which can extend forward as a flexible tube-like proboscis and allows the fish to scrape and collect small food particles, plant material, and detritus from submerged surfaces. Phractolaemus ansorgii inhabits slow-moving waters, forest pools, and swamps where dissolved oxygen may become very low, and its highly specialized swim bladder can function as an accessory respiratory organ that enables it to obtain oxygen from atmospheric air. In captivity, calm freshwater conditions, ample bottom area, subdued surroundings, and access to the water surface are important, while appropriately sized foods that can be gathered or grazed from the substrate help accommodate the specialized feeding behavior of Phractolaemus ansorgii.
