Apteronotus albifrons, also known as the black ghost knifefish, is a species of freshwater fish native to South America, including the Amazon and Orinoco River basins. It belongs to the family Apteronotidae, which includes several other species of knifefish. The black ghost knifefish is a popular aquarium fish due to its unique appearance and interesting behavior.

The black ghost knifefish has a distinctive black body and a long, ribbon-like tail that can be as long as the body itself. It has a blunt head with a small mouth and two small eyes, but it primarily uses its ability to detect electrical fields to navigate and locate prey. Like other knifefish, it produces a weak electrical field to sense its surroundings.

In the wild, black ghost knifefish are nocturnal and feed on small fish and invertebrates. In captivity, they should be fed a varied diet that includes meaty foods such as bloodworms, shrimp, and small pieces of fish.

Due to its unique appearance and interesting behavior, the black ghost knifefish has become a popular aquarium fish. However, it requires a large tank with plenty of hiding places and a gentle current to simulate its natural environment. It is also a relatively shy fish that prefers to hide during the day and become active at night.