freshwater
Molly
Poecilia sphenops
Stocky, streamlined body with rounded fins, featuring a uniform golden-yellow coloration and scales that shimmer slightly under aquarium lighting.
- Habitat
- Freshwater streams, rivers, and coastal brackish estuari…
- Size & weight
- Typically 2.5 to 4 inches (6 to 10 cm) in length, weighi…
- Diet
- Omnivorous feeder, grazing on algae, plant matter, small…
Identified More freshwater →
Learn more about Molly in the encyclopedia →Identify your own catch.
Get a report just like this from any photo, free.
Physical characteristics
Stocky, streamlined body with rounded fins, featuring a uniform golden-yellow coloration and scales that shimmer slightly under aquarium lighting.
Habitat & distribution
Freshwater streams, rivers, and coastal brackish estuaries, native to Central and South America, widely kept in freshwater aquariums globally.
Behavior
Active, peaceful, and social schooling fish that prefer to swim in groups in the middle and upper levels of the water column.
Diet
Omnivorous feeder, grazing on algae, plant matter, small crustaceans, and detritus.
Reproduction
Livebearer species (ovoviviparous); females give birth to free-swimming, fully formed young after internal fertilization and a gestation period of about 30 to 45 days.
Ecological role
Acts as a consumer of algae and small aquatic insects, helping to control local micro-organisms and serving as a prey base for larger aquatic predators.
Similar species
Platy (Xiphophorus maculatus), which has a shorter, stockier body profile and different natural color variations.
Identification tips
Look for the characteristic rounded dorsal fin, pointed snout, and continuous streamlined body shape typical of livebearing toothcarps.
Interesting facts
Mollies are remarkably adaptable and can tolerate varying levels of salinity, sometimes being successfully transitioned from fresh to brackish water environments.