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Onilahy River

The 883rd longest river in the world

km

Onilahy is a river in Atsimo-Andrefana and Anosy (Toliara Province), southern Madagascar. It flows down from the hills near Betroka to the Mozambique Channel. It empties at St. Augustin (23.5666667°S 43.75°E / -23.5666667, 43.75), and into the Bay of Saint-Augustin. Two species of cichlids are endemic to the river basin, but Ptychochromis onilahy is probably already extinct and the remaining range of Ptychochromoides betsileanus covers less than 10 square kilometres (3.9 mi2).

Flows through: Madagascar.

River data from Wikidata (CC0); lengths normalised to a common unit.

Other major rivers

  1. Amazon6,992 km
  2. Nile6,650 km
  3. Yangtze River6,300 km
  4. Bian River5,806 km
  5. Yellow River5,464 km
  6. Paraná River4,880 km
  7. River Congo4,700 km
  8. Mekong River4,350 km