Barred Topminnow

Found only in Cuba and the Isla de la Juventud, the Barred Topminnow is a small, delicate fish that favors slow-moving or still freshwater. It is typically spotted in areas with plenty of aquatic plants, such as ponds, lagoons, and rivers. This species swims in the middle of the water column rather than at the surface, often moving in small groups near the bottom. Growing to a maximum of 5 cm, these fish have side-compressed, almost diamond-shaped bodies. Their transparent, amber-olive skin reveals internal structures and is marked by distinct dark vertical bands. The triangular dorsal fin is particularly striking, featuring bold black edges and an orange center.

These omnivorous fish reach maturity quickly, with some individuals ready to breed by five weeks of age. They are livebearers, and females produce the smallest fry of any Cuban poeciliid fish. Rather than birthing a whole brood at once, the mother releases young individually over several days. Despite their resilience in breeding, this species faces a precarious future. Since the 1970s, dam construction has destroyed and fragmented their habitat. Surviving populations are further threatened by the introduction of predatory fish like Clarias gariepinus, as well as pollution from wastewater and solid waste. Agricultural runoff and livestock grazing also degrade the riverbanks where they live. The fish has not been seen in the wild since 2008, and recent surveys across dozens of sites have failed to find any survivors.