ichthyologist:

African Tigerfish (Hydrocynus vittatus)

With its interlocking razor sharp teeth and aggressive behavior, the African Tigerfish is sometimes dubbed the ‘African piranha’. A demersal, migratory freshwater species, Hydrocynus vittatus prefers warm, well-oxygenated water, mainly in larger rivers and lakes. The smaller individuals form roving schools of like-sized fish; aptly described as fierce and voracious but very large specimens may be solitary.