The pencil fishes are a family (Lebiasinidae) of freshwater fishes found in Costa Rica, Panama, and South America. They are usually small and are known as ornamental fishes in aquaria, including popular fishes such as the various pencil fish and the splashing tetra.

The pencil fishes are a family (Lebiasinidae) of freshwater fishes found in Costa Rica, Panama, and South America. They are usually small and are known as ornamental fishes in aquaria, including popular fishes such as the various pencil fish and the splashing tetra.