Citrus macroptera, natively known as shatkora or (Bengali: সাতকরা, pronounced as /syl/) cabuyao,[1] Melanesian papeda, or wild orange,[2] is a semi-wild species of citrus native to the Sylhet region (South Asia) of Bangladesh and the Barak Valley Division of the Indian state of Assam.
Some authorities consider C. macroptera to be a taxonomic synonym of C. hystrix (kaffir lime),[3] while others consider C. macroptera var. annamensis to be a synonym of C. hystrix, but not C. macroptera var. macroptera.
Citrus macroptera is so-named because of the large "wings" (-ptera) on the petiole, which is as large as the blade of the leaf.[2] The tree, which has thorns, can reach in height. Its fruit is about in diameter, has a fairly smooth, moderately thick rind, and is yellow when ripe. The pulp of the fruit is greenish-yellow and dry (does not produce much juice). The juice is very bitter, and somewhat sour.[2]
The species is sometimes divided into four varieties, or alternatively into three separate species, as follows:[4]
Citrus macroptera is cultivated on a small scale in home gardens in the northeast Indian states of Mizoram, Tripura, and Meghalaya, where its fruit is used for various purposes.[5] A cultivar of C. macroptera var. annamensis is grown in the Sylhet Division of northeastern Bangladesh.[6]
Citrus macroptera is also commercially cultivated in South Africa, Spain, and Tonga. In Spain the plant serves as a rootstock for other Citrus species.
In Bangladesh, especially Sylhet, the thick fleshy rind of Citrus macroptera is eaten as a vegetable, while the pulp is usually discarded because of its bitter-sour taste. The thick rind is cut into small pieces and cooked (either green or ripe) in beef, mutton, and fish curries, it is also used in Dal. The rind is often sun-dried for later cooking and consumption. The fruit is also pickled.
The oil of the annamensis cultivar is used in the perfume industry.[6]