Barred Topminnow Quintana atrizona

The Barred Topminnow, the only species in its genus, is (was?) endemic to small, well-vegetated ponds of western Cuba. A near-transparent fish, females are live-bearers reaching 5cm long; males reach 3cm. It is critically endangered from habitat fragmentation (dams, agriculture) and degradation/pollution (residential, agricultural, industrial), and introduction of foreign predatory fish. It may now even be extinct in the wild since expeditions/surveys since 2008 have failed to find any - although they are shy and, being almost transparent, difficult to find in their well-vegetated habitat.