Poecilia sphenops, commonly known as the black molly, is a freshwater fish native to the coastal waters of North and Central America. It typically inhabits brackish environments, such as estuaries and mangroves, and is known for its adaptability to varying salinity levels. The black molly is characterized by its dark coloration, which can range from black to gray, and it usually grows to about 3 to 4 inches in length. This species is popular in the aquarium trade due to its peaceful nature and ease of care. Poecilia sphenops is a livebearer, meaning it gives birth to live young rather than laying eggs. They thrive in groups and require a well-maintained tank with plenty of plants and hiding spots to mimic their natural habitat.