Coffea arabica (), also known as the Arabic coffee, is a species of flowering plant in the coffee and madder family Rubiaceae. It is believed to be the first species of coffee to have been cultivated and is currently the dominant cultivar, representing about 60% of global production. Coffee produced from the less acidic, more bitter, and more highly caffeinated robusta bean (C. canephora) makes up most of the remaining coffee production. Arabica coffee originates from and was first cultivated in Yemen, and documented by the 12th century. Coffea arabica is called () in Arabic. Taxonomy Coffea arabica was first described scientifically by Antoine de Jussieu, who named it Jasminum arabicum after studying a specimen from the Botanic Gardens of Amsterdam. Linnaeus placed it in its own genus Coffea in 1737. Coffea arabica is the only polyploid species of the genus Coffea, as it carries 4 copies of the 11 chromosomes (44 total) instead of the 2 copies of diploid species. Specifically, Coffea arabica is itself the result of a hybridization between the diploids Coffea canephora and Coffea eugenioides, thus making it an allotetraploid, with two copies of two different genomes. This hybridization event at the origin of Coffea arabica is estimated between 1.08 million and 543,000 years ago and is linked to changing environmental conditions in East Africa. Description Wild plants grow between tall, and have an open branching system; the leaves are opposite, simple elliptic-ovate to oblong, long and broad, glossy dark green. The flowers are white, 10–15 mm in diameter, and grow in axillary clusters. The seeds are contained in a drupe (commonly called a "cherry") 10–15 mm in diameter, maturing bright red to purple and typically containing two seeds, often called coffee beans. Distribution and habitat Endemic to the southwestern highlands of Ethiopia, Coffea arabica is now rare in Ethiopia, while many populations appear to be of mixed native and planted trees. Coffea arabica is today grown in dozens of countries between the Tropic of Capricorn and the Tropic of Cancer. It is commonly used as an understory shrub. It has also been recovered from the Boma Plateau in South Sudan. Coffea arabica is also found on Mount Marsabit in northern Kenya, but it is unclear whether this is a truly native or naturalised occurrence; recent studies support it being naturalised. The species is widely naturalised in areas outside its native land, in many parts of