red-tailed silverside

The red-tailed silverside, or zona (Bedotia geayi) is a species of Madagascar rainbowfish endemic to the Mananjary River drainage in Madagascar. It is threatened by habitat loss and introduced species. It has often been confused with the related B. madagascariensis, which is common in the aquarium trade. In addition to meristics, the two can be separated by the exact colour pattern on their tail fin (males of both typically have red in the tail) and the...