Tracing its biological heritage, Coffee trees belong to a sub-kingdom of vegetable scientifically known as Angiosperm or Angiospermae, which means that the plant reproduces through seeds enclosed in a box-like shaped ovaries, at the base of flower.
This sub-kingdom is divided into two classes namely Monocotyledoneæ and Dicotyledoneæ. This class division is based on the number of leaves that grows from seed. Since this plant has two small leaves, it is considered as Dicotyledoneæ.
Dicotyledoneæ is further divided into sub-classes based on the location of flower petals whether they are all in one part or divided into several parts. The flower petals of Coffee trees are arranged in one section forming a tubular arrangement making it belongs to Sympetalæ or Metachlamydeæ, which means the petals are united.
Next is what we called as categories. The Coffee plant belongs to a category known as Rubiales. This category is then divided into several families. Coffee trees are placed in the Rubiceæ family. This family member is known for its effects on the nervous system due to the content of caffeine which acts as the stimulant.
Under the Rubiales family, this caffeinated plant is identified under the genus Coffea and the sub-genus Eucoffea. The current classification results from the combination of several sub-genera with other genera. This sub-genus Eucoffea consists of various species of coffee trees, among the most famous are Coffea Arabica, Coffea Robusta, and Coffea Liberica.
This genus was first introduced by Carolus Linneaus, a Swedish botanist in the 18th century. Other botanists however disagreed with his view and are still debating for a more precise classification for this plant. This is reasonable given that this classification is very broad because in this genus there are over 500 genera and 6,000 species ranging from tropical trees and shrubs, with leaf sizes from 1cm to 40cm, and multiple colours from purple to yellow, and dark green. It is estimated that there are more than 100 species of coffee plants recorded around the world.
References:
1. https://pubs.rsc.org/en/content/chapterhtml/2019/bk9781782620044-00001
2. http://blog.italcoffee.com/botanical-classification-of-coffea-arabica/
3. https://www.academia.edu/43304492/DESKRIPSI_MORFOLOGI_ANATOMI_DAN_PERKEMBANGAN_KOPI_Coffea_sp
4. https://www.colonialcoffee.ca/whatiscoffee
