The black molly is the black cultivated breed of molly. As its name suggests, it has a black colouring: deep black scales covering its entire body along with a velvety sheen. There are also many colourful varieties with special tail fins.
 
Mollies generally come from Central and South America, and can be found from Mexico to Colombia. Black mollies belong to the live-bearing toothcarp family.
 
If kept correctly, mollies can grow to around 6 – 10 cm in length and live to be 5 years old. The males have larger dorsal fins than the females, making it easy to tell them apart. Like all livebearers, the males also have a modified anal fin, the gonopodium.