Yucatan Molly

Poecilia velifera

The Yucatan molly (Poecilia velifera) is a livebearing freshwater fish reaching up to 18 cm, with males developing a spectacularly large sail-like dorsal fin used in courtship displays. Males are typically greenish-blue with rows of orange and black spots, while the enormous dorsal fin can be as tall as the body when fully extended. Endemic to the coastal lagoons and cenotes of Mexico's Yucatan Peninsula, it inhabits brackish and freshwater environments at depths of 0 to 5 meters. Males perform elaborate courtship displays, erecting their sail fin and performing sideways swimming dances to attract females. This species is a popular aquarium fish and the ancestor of many cultivated molly varieties. Cenote divers in the Yucatan regularly encounter these beautiful fish, where the crystal-clear water allows appreciation of their magnificent dorsal fin displays.