Yucatan gambusia

Gambusia yucatana

The Yucatan gambusia (Gambusia yucatana) is a small livebearing fish reaching up to 6 cm. Females are larger than males and have a silvery-green body, while males are smaller with a modified anal fin (gonopodium) used for internal fertilization. Endemic to the Yucatan Peninsula of Mexico, Belize, and northern Guatemala, it inhabits cenotes, springs, coastal lagoons, and freshwater streams at depths of 0 to 3 meters. This hardy species is tolerant of variable water conditions and is often found in enormous schools in the shallow, sunlit zones of cenote entrances. It feeds on mosquito larvae, algae, and small invertebrates. Cenote divers routinely swim through clouds of these small fish when entering and exiting cenotes, where their silvery bodies catch and reflect the dramatic light beams penetrating the water.