The 
Molly (
Poecilia latipinna) is a popular 
freshwater aquarium fish species. It is a member of the 
Poecilidae family and is therefore 
live-bearing. It prefers hard water and can withstand a surprising degree of 
salinity. Indeed, mollies can be habituated to full-strength sea-water and live in a marine aquarium if need be. Mollies are more herbivorous than most aquarium fish and have a tendency to consume aquarium plants.
The species originates in the coastal areas of central America, on the Caribbean costline.
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