Taxonomy_of_the_coffee_plant

Plants are usually grouped in one genus based on common traits that justifies their close relationship within
that group. The smallest scientific relevant group is a species. A species is by definition a group of natural
populations, whose group members have the ability of reproduction, producing fertile offspring. This is also
called a reproductive community. If reproduction is no longer possible, e.g. in plants by a change in the
flower morphology of an individual, this could be the basis to form a new species.
However, always a combination of morphological traits are used in botanical classification. Closely related
species do not necessarily resemble each other, but as long as they share important traits, the relationship
is easy to recognize. This also applies for Coffea, where not all species are looking similar, as some are
very small trees, wheras others are very large ones, which depends on the ecological niche they exploit.
Especially for genera of worldwide distribution, ecology is a far more relevant force to shape the plant
compared to its genetic heritage. For instance, Rubiaceae have many tree species in the (sub)tropics,
whereas in the temperate regions they are herbs in order to survive the winter as seed.
This is an overview of the 125 species that are now forming the genus Coffea, which is also depicted in the
first part of all the latin names. The two relevant species in terms of coffee production are C. arabica and C.
canephora (marked in red). Coffea liberica is used only marginally for coffee production, partly because of
its large beans. Other species are grown only for local consumption, e.g. species on Madagascar.
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