Bedotia is a genus of rainbowfish-like silversides endemic to Madagascar, placed in its own family, Bedotiidae, distinct from the Australian-New Guinean rainbowfish family though sharing a similar elongated body and two separate dorsal fins. The atlas covers all 9 recognized species, from about 2 in to 3.5 in, found only in the island's rivers and streams. Males are the more colorful sex, developing a red- or orange-edged tail, dorsal, and anal fins with age, which is the basis for the group's common name, Madagascar rainbowfish.
Bedotia geayi, the red-tailed silverside, is a genuinely popular and easy community aquarium fish, active and peaceful in groups, and several of its relatives are traded on a smaller scale under similar Madagascar-rainbowfish names. The conservation status of the genus is severe: six of the nine species are Endangered, one Critically Endangered, one Vulnerable, and only one Near Threatened, effectively meaning the entire genus is considered at risk, which tracks with Madagascar's broader freshwater biodiversity crisis of deforestation, erosion, and introduced fish. Four of the nine species already carry a CARES-program listing, reflecting how much of this genus's future depends on hobbyist-maintained populations outside its native range.