The coffee genus (Coffea)
Coffea is a genus of 133 known wild species in Africa, Madagascar, Asia and Australasia. Two of them make almost all the world’s coffee, and most of the rest are threatened.
Across the chain: Sustainability · Science
Contents
In brief
- Coffea, the coffee genus of the family Rubiaceae, has 133 known species, the count of both the latest revision and Kew’s Plants of the World Online.3,4
- The world’s coffee farmers rely on two species, Arabica (C. arabica) and robusta (C. canephora); Liberica and excelsa coffee are a small but growing third crop.3
- Arabica is itself a hybrid of C. canephora and C. eugenioides; a 2024 genome study dates its origin to 350,000–610,000 years ago.6
- At least 60% of all coffee species are threatened with extinction, and 45% are not held in any germplasm collection.2
What the genus is#
Coffea is a genus of flowering plants in the coffee family, Rubiaceae.10,1 Every cup of coffee comes from the seeds of one of its species, but most of the genus is wild and never farmed.
The number of species keeps changing as botanists describe new ones and revise old ones. A 2006 conspectus listed 103 species.10 In 2011 the closely related genus Psilanthus was merged into Coffea, raising the count from 104 to 124 and extending the genus from Africa and Madagascar to tropical Asia and Australasia.1 The latest revision, in 2025, raised the count from 131 to 133 known species by reinstating two old names.3 Kew’s Plants of the World Online also lists 133 accepted species.4
Madagascar has by far the most species, 67. In mainland Africa, Cameroon has the most (18), followed by Tanzania (17).3
Two species make almost all the coffee#
The world’s coffee farmers, and with them the whole coffee supply chain, rely on two species: Arabica (C. arabica) and robusta (C. canephora).3 Arabica alone is the source of about 60% of coffee products worldwide.6
A third species group gives a small but growing share. Cultivation of liberica coffee (C. liberica) is increasing as climate challenges affect arabica and robusta, and as demand grows; excelsa (C. dewevrei) production is rising in India for similar reasons. Liberica is seeing a renaissance in Malaysia, Indonesia and Fiji. Excelsa draws attention in Uganda, South Sudan and Guinea because it crops under higher temperatures and longer dry spells than robusta, and its production is rising in India, Vietnam and Indonesia.3
Two West African species, C. stenophylla and C. affinis, were grown as small-scale crops more than 100 years ago and are now rare in the wild and no longer farmed.9
Arabica is a hybrid#
Arabica is not a “pure” species. It is an allotetraploid hybrid of C. eugenioides and C. canephora. A 2024 genome study dates the founding hybridisation to 350,000–610,000 years ago and finds several bottlenecks before domestication, which left Arabica with little genetic variation.6 Earlier estimates of its age differed widely (see Contested).11 How that narrow base was split into the varieties grown today is the subject of Arabica varieties and their lines.
Wild species at risk#
Applying the IUCN Red List criteria to all 124 species then known, a 2019 study found that at least 60% of coffee species are threatened with extinction, 45% are not held in any germplasm collection, and 28% are not known to occur in any protected area.2 Wild Arabica itself is listed as Endangered.5 Its assessment depends on climate change: with climate projections included it is Endangered; without them it would be Least Concern.7
Wild species are critical for developing the coffee crop and so for the sustainability of coffee production.2 Forgotten crop species such as C. stenophylla may carry useful traits, including taste, disease resistance and climate resilience.9 The index below lists every accepted species, where it grows wild and its Red List category. Search a name or a country, filter by region, or tap a category in the bar to see only those species.
Coffee species index
All 133 accepted coffee species: where each grows wild and how threatened it is. Search a name or a country, filter by region and Red List category.
Extinction risk (IUCN Red List)
133 accepted species in Plants of the World Online (Kew), accessed 12 October 2026; native regions grouped by us. The hybrid C. ×heterocalyx is not counted. Red List categories: IUCN Red List version 2026-1 via GBIF (C. liberica checked on the IUCN Red List website, 12 October 2026: Least Concern); 2 names without a clean match are shown as “Not matched”.
How the genus grew: Psilanthus merged#
Coffea and Psilanthus were long kept apart, but DNA sequences from four plastid regions and the nuclear ITS region showed that the sequence divergence between their species is negligible, with strong indications that neither genus is monophyletic (a group made of one ancestor and all its descendants). Only one critical feature separated them: Coffea has a long, protruding style, Psilanthus a short one hidden inside the flower. On this evidence Psilanthus was merged into Coffea in 2011.1 The same study informally named a group of closely related species the “Coffea liberica alliance”.1
Liberica split into three#
Liberica and excelsa coffee were long treated as two varieties of one species, C. liberica. Genomic, morphological and distribution data published in 2025 support three separate species instead: C. liberica (Liberica), C. dewevrei (excelsa) and C. klainei, a poorly known species previously treated as a synonym.3
| C. liberica (Liberica) | C. dewevrei (excelsa) | C. klainei | |
|---|---|---|---|
| Native range | Upper West Africa: Sierra Leone, Liberia, Ivory Coast, Ghana, Nigeria | Central Africa: Republic of the Congo, Cameroon, DR Congo, Central African Republic, South Sudan, Uganda | West-Central Africa: Cameroon, Gabon, Republic of the Congo, Angola (Cabinda) |
| Mean leaf length | 22.8 cm | 29.5 cm | 23.9 cm |
| Mean leaf width | 8.2 cm | 14 cm | 8.7 cm |
| Mean seed length × width | 12.6 × 8.4 mm | 9.3 × 6.6 mm | – |
| Mean parchment thickness | 0.57 mm | 0.31 mm | – |
| Flowers | Six- to nine-parted or more | Usually five-parted; more flowers per axil | Few per inflorescence, unbranched |
Source for the table: Davis et al. 2025.3 Experienced farmers and buyers tell Liberica and excelsa apart by leaf size and shape, fruit and seed size and yield, which matches the measurements.3
A heat-tolerant relative: stenophylla#
C. stenophylla is native to Guinea, Sierra Leone and Ivory Coast. Fieldwork published in 2020 rediscovered it in Sierra Leone, where it had not been recorded in the wild since 1954.9 Sensory tests confirmed historical reports of a superior flavour and found a profile similar to high-quality Arabica. The species grows and crops at a mean annual temperature 6.2–6.8 °C higher than Arabica, under the same climatic range as robusta and Liberica.8 The same research group found that hybridisation is possible across all the major groups of key African Coffea species, which matters for breeding.9
The Red List in numbers#
Of the 133 accepted species, 131 can be matched cleanly to the IUCN Red List (version 2026-1). Among those, 12 are Critically Endangered, 40 Endangered and 23 Vulnerable: 75 threatened species, or 57% of the matched names. Another 9 are Near Threatened, 25 Least Concern, 14 Data Deficient and 8 Not Evaluated.5,4,12 One name was corrected by hand: the GBIF copy of the Red List shows C. liberica as not evaluated, but the IUCN Red List itself lists it as Least Concern.12 The 2019 assessment, done on 124 species with the full assessment data, gives at least 60%.2 In 2006, 72 of 103 species (about 70%) were assessed as threatened, through a decline in the quantity and quality of their habitat.10
The counts above are our tally of the Red List data matched to Plants of the World Online names; two names, C. dewevrei and C. klainei, reinstated in 2025, have no clean match yet.
Reference table: species grown for coffee#
| Species | Coffee name | Native range (POWO) | Red List | Role |
|---|---|---|---|---|
| C. arabica | Arabica | Ethiopia, Kenya, South Sudan | Endangered | Main crop, about 60% of coffee products6 |
| C. canephora | Robusta | West and Central Africa to Uganda and Tanzania | Least Concern | Main crop3 |
| C. liberica | Liberica | Upper West Africa | Least Concern12 | Minor crop, growing3 |
| C. dewevrei | Excelsa | Central Africa | Not matched | Minor crop, growing3 |
| C. stenophylla | Stenophylla | Guinea, Sierra Leone, Ivory Coast, Liberia | Vulnerable | Former crop; heat-tolerant, Arabica-like flavour9,8 |
| C. affinis | – | Guinea, Sierra Leone, Ivory Coast | Data Deficient | Former crop9 |
Native ranges from Plants of the World Online4; Red List categories from version 2026-1.5
Key studies#
Davis et al., 2019 – Extinction risk of all coffee species. Applies the IUCN Red List criteria to every wild coffee species then known (124) and runs a gap analysis for germplasm collections and protected areas. Finds that at least 60% of species are threatened and many are conserved nowhere, and devises a priority system for crop wild relatives.
Davis et al., 2011 – Psilanthus merged into Coffea. Uses plastid and nuclear DNA sequences and morphology to show that Coffea and Psilanthus cannot be kept apart. The merger brings the genus to Asia and Australasia and raises the species count from 104 to 124.
Davis et al., 2025 – Liberica is three species. Combines genome-wide data, leaf, flower, fruit and seed measurements and cleaned distribution records to separate Liberica, excelsa and C. klainei, with consequences for breeding and conservation.
Salojärvi et al., 2024 – The Arabica genome. Presents chromosome-level genomes of Arabica and its two parent species and dates the hybrid origin of Arabica. Traces the bottlenecks behind its narrow diversity and the breeding history of modern varieties.
Coffearium (2026). The coffee genus (Coffea). Coffearium – The open coffee compendium. Retrieved 22 October 2026, from https://coffearium.org/entries/coffea-genus/
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title = {{The coffee genus (Coffea)}},
year = {2026},
howpublished = {Coffearium -- The open coffee compendium},
url = {https://coffearium.org/entries/coffea-genus/},
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}Entries are updated when the evidence changes; the retrieval date tells your readers which version you used.
Sources
- ADavis, A. P.; Tosh, J.; Ruch, N.; Fay, M. F. (2011). Growing coffee: Psilanthus (Rubiaceae) subsumed on the basis of molecular and morphological data; implications for the size, morphology, distribution and evolutionary history of Coffea. Botanical Journal of the Linnean Society 167(4), 357–377. doi:10.1111/j.1095-8339.2011.01177.x · other copies
- ADavis, A. P.; Chadburn, H.; Moat, J.; O’Sullivan, R.; Hargreaves, S.; Nic Lughadha, E. (2019). High extinction risk for wild coffee species and implications for coffee sector sustainability. Science Advances 5(1), eaav3473. doi:10.1126/sciadv.aav3473 · other copies
- ADavis, A. P.; Shepherd-Clowes, A.; Cheek, M.; Moat, J.; Luo, D. W.; Kiwuka, C.; Kalema, J.; et al. (2025). Genomic data define species delimitation in Liberica coffee with implications for crop development and conservation. Nature Plants 11, 1729–1738. doi:10.1038/s41477-025-02073-y · other copies
- ARoyal Botanic Gardens, Kew (2026). Coffea L.. Plants of the World Online (World Checklist of Vascular Plants).
- AIUCN (2026). The IUCN Red List of Threatened Species, version 2026-1 (via GBIF.org). International Union for Conservation of Nature; GBIF, licence CC BY 4.0. doi:10.15468/0qnb58 · other copies
- ASalojärvi, J.; Rambani, A.; Yu, Z.; Guyot, R.; et al. (2024). The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars. Nature Genetics 56(4), 721–731. doi:10.1038/s41588-024-01695-w · other copies
- AMoat, J.; Gole, T. W.; Davis, A. P. (2019). Least concern to endangered: Applying climate change projections profoundly influences the extinction risk assessment for wild Arabica coffee. Global Change Biology 25(2), 390–403. doi:10.1111/gcb.14341 · other copies
- ADavis, A. P.; Mieulet, D.; Moat, J.; Sarmu, D.; Haggar, J. (2021). Arabica-like flavour in a heat-tolerant wild coffee species. Nature Plants 7(4), 413–418. doi:10.1038/s41477-021-00891-4 · other copies
- ADavis, A. P.; Gargiulo, R.; Fay, M. F.; Sarmu, D.; Haggar, J. (2020). Lost and Found: Coffea stenophylla and C. affinis, the Forgotten Coffee Crop Species of West Africa. Frontiers in Plant Science 11, 616. doi:10.3389/fpls.2020.00616 · other copies
- ADavis, A. P.; Govaerts, R.; Bridson, D. M.; Stoffelen, P. (2006). An annotated taxonomic conspectus of the genus Coffea (Rubiaceae). Botanical Journal of the Linnean Society 152(4), 465–512. doi:10.1111/j.1095-8339.2006.00584.x · other copies
- AScalabrin, S.; Toniutti, L.; Di Gaspero, G.; et al.; Bertrand, B. (2020). A single polyploidization event at the origin of the tetraploid genome of Coffea arabica is responsible for the extremely low genetic variation in wild and cultivated germplasm. Scientific Reports 10, 4642. doi:10.1038/s41598-020-61216-7 · other copies
- AIUCN (2026). Coffea liberica, The IUCN Red List of Threatened Species. International Union for Conservation of Nature.
Tier A · authoritative · B · trade and expert · C · general. Supporting quotes for every source are in the data version of this entry. If a publisher’s site refuses access, try the doi link or “other copies”.
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