New coffee species from Madagascar

Earlier this year, the news of the "discovery" of a caffeine-free species of coffee from the Cameroon created a bit of a stir. This species was actually first collected in 1983, but remained unstudied and not described to science until 2008 [1], at which point it made headlines when it made a 2009 top ten list of new species. I wrote about it here.

Similiarly, the Royal Botanical Gardens at Kew just announced some recent achievements, among which was the "discovery" of six new species in the genus Coffea from Madagascar. Again, these species were not necessarily just discovered but were described in a paper published in 2008[2].  Coffea ambongenis, for example, was first collected in 1841 but not described, was rediscovered in 1999, and is now published as a new species.

There are 103 described species of Coffea in the world, and the Madagascar species are part of the Coffea subgenus Baracoffea, which now stands at 9 species. In addition to species in this subgenus being deciduous rather than evergreen like all other coffee species, some have unusual morphological characteristics. Here is a very brief run-down.

• C. ambongensis and C. boinensi: Very large fruit, in C. ambongensis often larger than 2.5 cm long. C. boinensi was first collected in 1994. 
• C. bissetiae: Underside of leaves and fruit hairy.
• C. labatii and C. pterocarpa: Unusual winged fruit. C. labatii, first collected in 1992, has 12 to 18 "wings" per fruit. C. pterocarpa (first collected in 1954) has 16 to 20 wings, and is pictured at right in a photo by Aaron Davis from Kew; an informative accompanying article is here. One theory as to the function of the wings is that it helps the fruit float, and these species occur in regularly-flooded karst limestone habitats.
• C. namorokensis: First collected in 2000, but not identified as a new species. Also has hairy fruit and leaves.

None of the new species have been tried as a beverage, and it is unlikely they will ever be commercialized.  All are rare: near-threatened to critically endangered, and Madagascar forests are among the most exploited and threatened in the world today.

[1] Stoffelen, P., M. Noirot, E. Couturon & F. Anthony. 2008. A new caffeine-free coffee from Cameroon. Botanical Journal of the Linnean Society 158: 67-72.

[2] Davis, A. P, & F. Rakotonasolo. 2008. A taxonomic revision of the baracoffea alliance: nine remarkable Coffea species from western Madagascar. Botanical Journal of the Linnean Society, 158 (3), 355-390 DOI: 10.1111/j.1095-8339.2008.00936.x