Black Molly

Physical Characteristics

This fish exhibits a solid matte black coloration across its entire body and fins. It has a short-finned, streamlined body shape with a rounded caudal (tail) fin and a small dorsal fin. It belongs to the family Poeciliidae and possesses the typical upturned mouth of a surface feeder.

Habitat & Distribution

Natively found in fresh and brackish waters across Central and South America, particularly in Mexico and Colombia. They inhabit coastal streams, ponds, and lagoons, and are known for their high tolerance to varying levels of salinity.

Size & Weight

Typically reaches an adult length of 3 to 5 inches (7.5 to 12.5 cm). They are lightweight fish, rarely exceeding a few grams in weight.

Similar Looking Species

Similar species include the Sailfin Molly (Poecilia latipinna), which is distinguished by a much larger, sail-like dorsal fin, and the Black Guppy, which is generally smaller with a much more elongated and flowing tail structure.

Ecological Role

They are omnivorous live-bearers that primarily feed on algae, small insects, and detritus, helping to control algae growth in their environments. They serve as a prey source for larger fish and birds. Their conservation status is currently listed as Least Concern, as they are prolific breeders with stable populations.

Identified on: 2/18/2026

Mode: Standard