Senegal Bichir, Polypterus senegalus, is a primitive freshwater fish native to tropical Africa, where it has a broad distribution across the Nile Basin and numerous river systems of West and Central Africa. It inhabits slow-moving rivers, floodplains, swamps, marshes, and shallow vegetated waters where submerged wood, aquatic vegetation, and muddy or sandy substrates provide shelter. These environments may experience low dissolved oxygen, something bichirs are exceptionally well adapted to thanks to their paired lungs and ability to breathe atmospheric air. Adult Senegal Bichirs typically reach about 10 to 12 inches in captivity, although larger individuals are possible. The body is long, muscular, and almost reptilian in appearance, covered in tough, diamond-shaped ganoid scales that give the fish an armored, prehistoric look. Coloration typically ranges from pale gray and silver to olive-gray or beige, often with a lighter cream-colored underside. Instead of a single continuous dorsal fin, the back carries a row of individual finlets, each supported by its own spine. Large paddle-like pectoral fins are used almost like limbs as the fish moves across the bottom, while the broad head, small eyes, and prominent nostrils complete its unmistakably ancient appearance. Bichirs belong to one of the oldest surviving lineages of ray-finned fishes, and the Senegal Bichir looks every bit the living fossil. A tank of at least 75 gallons is recommended for an adult, with larger aquariums preferred for multiple bichirs or community setups. Floor space is particularly important because Senegal Bichirs spend most of their time near the bottom. Fine sand or smooth substrate is ideal, along with driftwood, caves, rocks, and shaded retreats. A tightly secured lid is absolutely essential. Bichirs are remarkably capable escape artists and can squeeze through surprisingly small openings. A small air space should remain between the water surface and lid because they must periodically surface to breathe atmospheric air. Water conditions should remain stable and clean. Temperatures between 75 and 82 degrees Fahrenheit are appropriate, with a pH range of approximately 6.0 to 8.0 and soft to moderately hard water. Senegal Bichirs are hardy and adaptable, but strong biological filtration and regular water changes are important because of their size and protein-rich diet. Water movement should be gentle to moderate rather than excessively strong. Senegal Bichirs are carnivorous predators. In nature they consume insects, worms, crustaceans, small fish, amphibians, and other aquatic animals. In the aquarium they readily accept sinking carnivore pellets, shrimp, krill, earthworms, bloodworms, mussel, and other appropriately sized meaty foods. Many become enthusiastic feeders and quickly learn to emerge when food is offered. Feeder fish are unnecessary and are best avoided because of their potential to introduce parasites and disease. Temperament is generally peaceful toward fish that cannot be swallowed. Senegal Bichirs are not particularly aggressive, but they are opportunistic predators and should never be trusted with small tankmates. Any fish narrow enough to fit into a bichir's mouth should eventually be considered potential prey, particularly after the lights go out. Suitable tankmates include medium to large peaceful cichlids, larger rainbowfish, robust catfish, larger characins, and other bichirs of compatible size. Breeding is possible in captivity but remains relatively uncommon in typical home aquariums. During courtship, males use their enlarged anal fin to receive and fertilize eggs from the female before the adhesive eggs are scattered among vegetation. Adults provide no parental care and may consume both eggs and fry. Young bichirs initially possess prominent external gills, giving the juveniles an especially unusual amphibian-like appearance. Polypterus senegalus is one of the most accessible members of an extraordinary ancient lineage of fishes. Its armored scales, individual dorsal finlets, lung-breathing ability, deliberate movements, and almost reptilian appearance make the Senegal Bichir unlike virtually anything else commonly kept in freshwater aquariums. Despite its predatory nature, its generally calm temperament and impressive hardiness make it an outstanding centerpiece for aquarists prepared to provide adequate space and appropriately sized tankmates.
