sailfin molly

fish

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 13, 2026

Quick Summary

The sailfin molly is a tropical fish belonging to the genus Poecilia within the live-bearer family, Poeciliidae. These fish are popular in aquariums due to their hardiness and attractive appearance, typically measuring between 2 to 5 inches in length.1

Sailfin mollies, specifically P. latipinna and P. velifera, are known for their shiny, bluish coloration. A distinguishing feature is the male's large, prominent dorsal fin, which gives the species its name. The term "sailfin" also refers to a specific type of topminnow, Mollienisia latipinna, found in the southern U.S. and Mexico, characterized by olive-green bodies with black markings and vibrantly colored fins. Various color varieties exist, including black mollies, which can be of any of the mentioned species.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

molly
…is normally grayish, and the sailfin mollies (P. latipinna and P. velifera), which are shiny and bluish and are noted for the large, showy dorsal fin of the male. Hybrids are also known, including P. formosa, a so-called species that is always female, resulting from a cross between P. sphenops…
Read More
…is normally grayish, and the sailfin mollies (P. latipinna and P. velifera), which are shiny and bluish and are noted for the large, showy dorsal fin of the male. Hybrids are also known, including P. formosa, a so-called species that is always female, resulting from a cross between P. sphenops…
Read More