While Arabica is native to Ethiopia, Coffea canephora (also known as Robusta) is native to the lowland forests of West Africa.
Robusta is a hardier plant than Arabica and more resistant to disease and insect damage. European colonists, who wished to expand the coffee markets in France and Portugal, were the first to cultivate Robusta. It can be grown at altitudes between sea level and 1000 meters and is the coffee most often grown in West Africa and East Asia.
Robusta has less flavour and more bitterness than Arabica coffee. It is usually used in the mass-produced coffees most often sold in supermarkets. It is also widely used in European coffees because it gives a better "crema" then Arabica coffee.
The name "Robusta" actually refers to a variety of the species Coffea canephora. The Robusta plant grows about 10 meters in height and has a shallow root system. The fruit takes about 11 months to mature and is round in shape. Its seeds are oval and smaller than Arabica beans.
The political economy of government price regulation in the robusta coffee market of Cameroon (Staff Paper) by James Jerome Gockowski.
Robusta Coffee Cultivation: Husbandry, management, processing by Erik De Bock.
Studies and notes on the comparative cultivation of the Arabica coffee tree and the Robusta coffee tree in Java by W. Bally