{
  "id": "liberica-and-excelsa",
  "url": "https://coffearium.org/entries/liberica-and-excelsa/",
  "license": "CC-BY-4.0",
  "title": "Liberica and excelsa",
  "summary": "Two large-fruited African coffee trees, long treated as one species. Planted in Asia after leaf rust in the late 19th century, they are now a tiny but growing crop valued for heat and drought tolerance.",
  "domain": "botany",
  "kind": "Species",
  "stage": "plant",
  "topics": [
    "history"
  ],
  "topicSections": {},
  "lang": "en",
  "status": "verified",
  "reviewer": "Coffearium verification pass",
  "lastVerified": "2026-10-16T00:00:00.000Z",
  "updated": "2026-10-16T00:00:00.000Z",
  "added": "2026-10-16T00:00:00.000Z",
  "brief": [
    "A 2025 genomic study splits liberica coffee into three species, *Coffea liberica* (liberica), *C. dewevrei* (excelsa) and *C. klainei*; earlier works treated excelsa as a variety.<sup><a href=\"#src-s1\">1</a>,<a href=\"#src-s2\">2</a></sup>",
    "The coffee industry turned to liberica against leaf rust in about 1875–1900, then to robusta from the early 1900s.<sup><a href=\"#src-s2\">2</a></sup>",
    "Global production of liberica and excelsa together is probably below 1,000 tonnes, about 0.01% of world coffee exports (2025 estimate).<sup><a href=\"#src-s1\">1</a></sup>",
    "Excelsa is valued for cropping under higher temperatures and longer dry spells than robusta, and Ugandan farmers have been switching to it.<sup><a href=\"#src-s1\">1</a>,<a href=\"#src-s2\">2</a></sup>",
    "Liberica fruits have a 4–9.5 mm pulp, against 2–3.5 mm in excelsa, which makes liberica harder to process.<sup><a href=\"#src-s1\">1</a>,<a href=\"#src-s2\">2</a></sup>"
  ],
  "quickFacts": [
    {
      "label": "Species",
      "value": "C. liberica (liberica), C. dewevrei (excelsa), since 2025"
    },
    {
      "label": "Native range",
      "value": "Liberica Upper West Africa; excelsa Central Africa"
    },
    {
      "label": "Habit",
      "value": "Tree; excelsa around 10 m or more in Uganda"
    },
    {
      "label": "Liberica cultivation",
      "value": "Mostly 10–500 m, mean annual temperature e.g. 24–27 °C"
    },
    {
      "label": "World production",
      "value": "Probably < 1,000 t (2025 estimate)"
    },
    {
      "label": "Red List (C. liberica)",
      "value": "Least Concern (as cited in 2025); Vulnerable suggested in 2025"
    }
  ],
  "aka": [
    "Liberica coffee",
    "Excelsa coffee",
    "Liberian coffee",
    "Coffea liberica",
    "Coffea dewevrei",
    "Barako"
  ],
  "linkTerms": [
    "liberica",
    "excelsa",
    "C. liberica",
    "C. dewevrei",
    "C. klainei",
    "Coffea liberica",
    "Coffea dewevrei",
    "Coffea excelsa",
    "barako",
    "kapeng barako"
  ],
  "related": [
    "coffea-genus",
    "coffea-arabica",
    "coffea-canephora",
    "coffee-leaf-rust",
    "arabica-varieties",
    "coffee-cherry-anatomy",
    "site-selection-and-climate",
    "pulping",
    "stenophylla-and-wild-relatives"
  ],
  "contested": [
    "Species or varieties: a 2023 review describes the consensus of taxonomic study as one species, *C. liberica*, with two varieties, var. *liberica* and var. *dewevrei*<sup><a href=\"#src-s2\">2</a></sup>; a 2025 genomic study supports three species, *C. liberica*, *C. dewevrei* and *C. klainei*.<sup><a href=\"#src-s1\">1</a></sup>",
    "Liberica and excelsa as rootstocks: a 2001 grafting study, as summarised in 2017, found low compatibility with arabica scions and smaller beans with less aroma<sup><a href=\"#src-s5\">5</a></sup>; a 2023 review reports *C. liberica* in the broad sense in use as a rootstock for arabica in Hawaii, for nematode resistance, yield and survival.<sup><a href=\"#src-s2\">2</a></sup>"
  ],
  "corrections": [],
  "sources": [
    {
      "id": "s1",
      "title": "Genomic data define species delimitation in Liberica coffee with implications for crop development and conservation",
      "authors": "Davis, A. P.; Shepherd-Clowes, A.; Cheek, M.; Moat, J.; Luo, D. W.; Kiwuka, C.; Kalema, J.; Tchiengué, B.; Viruel, J.",
      "year": 2025,
      "publisher": "Nature Plants 11, 1729–1738",
      "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12449269/",
      "doi": "10.1038/s41477-025-02073-y",
      "tier": "A",
      "quote": "Today, global production of C. liberica and C. dewevrei is probably less than 1,000 metric tons (mt).",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s2",
      "title": "A review of the indigenous coffee resources of Uganda and their potential for coffee sector sustainability and development",
      "authors": "Davis, A. P.; Kiwuka, C.; Faruk, A.; Mulumba, J.; Kalema, J.",
      "year": 2023,
      "publisher": "Frontiers in Plant Science 13, 1057317",
      "url": "https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1057317/pdf",
      "doi": "10.3389/fpls.2022.1057317",
      "tier": "A",
      "quote": "It is worth noting that wild species were used to sustain the global coffee industry in response to the devasting influence of CLR at the end of nineteenth century, firstly using C. liberica, from c. 1875–1900, and then C. canephora from the early 1900s onwards (McCook, 2014; Davis et al., 2019; McCook, 2019; Davis et al., 2022).",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s3",
      "title": "Phenotypic Variability of Liberoid Coffee (C. liberica and C. dewevrei) Across Sumatera and Javanese Landscapes: Foundational Insights for Coffee-based Agroforestry",
      "authors": "Faronny, D. I.; Rahma, M. J.; Pradhana, A.; Nurrofik, A.; Sunarharum, W. B.; Hakim, L.; Soemarno; Nillian, E.; Mahatmanto, T.",
      "year": 2026,
      "publisher": "Tropical Life Sciences Research (early view, 26 August 2026)",
      "url": "https://ejournal.usm.my/tlsr/article/download/7664/early_view/13370",
      "tier": "A",
      "quote": "as a biological solution to the leaf rust epidemic (Hemileia vastatrix)",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s4",
      "title": "The Coffee Tree – Genetic Diversity and Origin",
      "authors": "Herrera, J. C.; Lambot, C.",
      "year": 2017,
      "publisher": "In: Folmer, B. (ed.), The Craft and Science of Coffee, Academic Press, ch. 1, pp. 1–16",
      "url": "https://doi.org/10.1016/B978-0-12-803520-7.00001-3",
      "doi": "10.1016/B978-0-12-803520-7.00001-3",
      "tier": "B",
      "quote": "By comparison, C. liberica Hiern, the third most important cultivated species, was planted to a lesser extent than C. canephora because of its recognized sensitivity to Fusarium xylarioides even if this species showed a clustered fruit maturation, contributing to a better coffee quality and higher seed weight.",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s5",
      "title": "Cultivating Coffee Quality – Terroir and Agro-Ecosystem",
      "authors": "Lambot, C.; Herrera, J. C.; Bertrand, B.; Sadeghian, S.; Benavides, P.; Gaitán, A.",
      "year": 2017,
      "publisher": "In: Folmer, B. (ed.), The Craft and Science of Coffee, Academic Press, ch. 2, pp. 17–49",
      "url": "https://doi.org/10.1016/B978-0-12-803520-7.00002-5",
      "doi": "10.1016/B978-0-12-803520-7.00002-5",
      "tier": "B",
      "quote": "These two species revealed a low compatibility with Arabica scions.",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s6",
      "title": "Coffea liberica Bull ex Hiern",
      "authors": "Sosef, M. S. M.; Boer, E.",
      "year": 2000,
      "publisher": "In: van der Vossen, H. A. M.; Wessel, M. (eds), Plant Resources of South-East Asia No 16: Stimulants, PROSEA Foundation, Bogor (PROSEA database record)",
      "url": "https://prosea.prota4u.org/view.aspx?id=608",
      "tier": "B",
      "quote": "Liberica coffee fruits present difficulties in pulping because of the large fruit size and the hard fruit skin.",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s7",
      "title": "Our coffee heritage",
      "authors": "Philippine Coffee Board Inc.",
      "publisher": "Philippine Coffee Board Inc.",
      "url": "https://philcoffeeboard.com/philippine-coffee/",
      "tier": "B",
      "quote": "Philippine Liberica is known locally as Barako/Baraco, a coffee bean that produces a distinctively robust and powerful cup.",
      "accessed": "2026-10-16T00:00:00.000Z"
    },
    {
      "id": "s8",
      "title": "Excelsa and Liberica coffee development",
      "authors": "Royal Botanic Gardens, Kew",
      "publisher": "Royal Botanic Gardens, Kew (project page)",
      "url": "https://www.kew.org/science/our-science/projects/excelsa-and-Liberica-coffee-development",
      "tier": "B",
      "quote": "The project is focused on excelsa coffee in Uganda,",
      "accessed": "2026-10-16T00:00:00.000Z"
    }
  ],
  "markdown": "## Two coffees from one old name\n\nMost coffee comes from two species, arabica (*Coffea arabica*) and robusta (*C. canephora*).<sup><a href=\"#src-s1\">1</a></sup> Liberica and excelsa are two further coffee trees from the African lowlands. Until 2025 most botanists treated them as one species, *C. liberica*.<sup><a href=\"#src-s2\">2</a>,<a href=\"#src-s1\">1</a></sup>\n\nA 2025 study of their genomes, leaves, flowers, fruits and seeds treats them as separate species. Liberica keeps the name *C. liberica*. Excelsa becomes *C. dewevrei*.<sup><a href=\"#src-s1\">1</a></sup> A third, little-known species, *C. klainei*, was split off at the same time.<sup><a href=\"#src-s1\">1</a></sup>\n\nLiberica is native to Upper West Africa, from Sierra Leone and Liberia to Nigeria. Excelsa is native to Central Africa, from Cameroon to South Sudan and Uganda.<sup><a href=\"#src-s1\">1</a></sup> In the trade, the name “excelsa” is often given to small-seeded liberica, especially in Asia.<sup><a href=\"#src-s2\">2</a></sup> So a coffee sold as excelsa is not always *C. dewevrei*.\n\n## Trees with large fruit\n\nUnlike arabica and robusta, excelsa grows into a medium-sized tree, around 10 m or more in Uganda.<sup><a href=\"#src-s2\">2</a></sup> Its leaves are large: 29.5 cm long and 14 cm wide on average. Liberica leaves average 22.8 × 8.2 cm.<sup><a href=\"#src-s1\">1</a></sup>\n\nLiberica fruits are large. They measure up to 3.4 cm long, with a pulp (the fleshy layer under the skin) 4–9.5 mm thick.<sup><a href=\"#src-s1\">1</a></sup> Excelsa fruits are smaller, with a thinner pulp and smaller seeds. They grow in tight clusters along the branches.<sup><a href=\"#src-s1\">1</a>,<a href=\"#src-s2\">2</a></sup>\n\n<figure>\n<div data-figure=\"liberica-and-excelsa-fruit-size\"></div>\n<figcaption>Liberica fruits are longer and wider than excelsa fruits and have a thicker pulp. Ranges from the 2025 species study.<sup><a href=\"#src-s1\">1</a></sup></figcaption>\n</figure>\n\nThe fruits also take longer to ripen. In Uganda, excelsa fruit develops for longer than arabica and robusta fruit. Its main harvest, from January to April, does not overlap with theirs.<sup><a href=\"#src-s2\">2</a></sup>\n\n## From rescue crop to niche\n\nIn the late 19th century, coffee leaf rust devastated arabica growing. The coffee industry turned to liberica from about 1875 to 1900, then to robusta from the early 1900s.<sup><a href=\"#src-s2\">2</a></sup> A 2026 study of liberica in Indonesia dates its wide spread to the 1870s, as an answer to the rust.<sup><a href=\"#src-s3\">3</a></sup> According to a 2000 plant handbook, liberica also proved susceptible to leaf rust there, and robusta replaced it.<sup><a href=\"#src-s6\">6</a></sup>\n\nLiberica stayed in South-East Asia. It is grown in the lowlands of Malaysia, the Philippines and Indonesia.<sup><a href=\"#src-s1\">1</a></sup> In the Philippines, liberica is known locally as barako.<sup><a href=\"#src-s7\">7</a></sup>\n\nExcelsa has a newer story. In lowland Uganda, farmers have shifted to it, perhaps since at least the 1980s. The 2023 review links this to disease, pests and drought in robusta.<sup><a href=\"#src-s2\">2</a></sup> A similar increase is reported in South Sudan.<sup><a href=\"#src-s2\">2</a></sup> As of 2025, liberica is seeing a renaissance in Malaysia, Indonesia and Fiji, and attention on excelsa centres on Uganda, South Sudan and Guinea.<sup><a href=\"#src-s1\">1</a></sup>\n\n## Heat and drought\n\nAccording to the 2025 study, excelsa can crop under higher temperatures and longer dry spells than robusta.<sup><a href=\"#src-s1\">1</a></sup> In Uganda, the places where it is recorded have a modelled mean annual temperature of 24.4 °C. Robusta records there average 21.8 °C.<sup><a href=\"#src-s2\">2</a></sup> The review says excelsa may be more heat tolerant than robusta, but field trials are needed.<sup><a href=\"#src-s2\">2</a></sup> Liberica is farmed mostly in warm, wet lowlands, at 10–500 m.<sup><a href=\"#src-s1\">1</a></sup>\n\n<figure>\n<div data-figure=\"liberica-and-excelsa-temperature\"></div>\n<figcaption>Mean annual temperatures where arabica, robusta, excelsa and liberica grow, as reported in a 2023 review and a 2025 study. The Uganda values are modelled for recorded locations, not measured optima.<sup><a href=\"#src-s2\">2</a>,<a href=\"#src-s1\">1</a></sup></figcaption>\n</figure>\n\nAccording to the 2025 study, liberica cultivation is increasing as climate change puts pressure on arabica and robusta. Excelsa production in India is rising for the same reason.<sup><a href=\"#src-s1\">1</a></sup> Royal Botanic Gardens, Kew, runs a research project on excelsa in Uganda with Ugandan partners.<sup><a href=\"#src-s8\">8</a></sup>\n\n## Processing and the cup\n\nLiberica fruits are hard to pulp (strip of skin and pulp), because they are large and have a hard skin.<sup><a href=\"#src-s6\">6</a></sup> Excelsa can be processed with standard procedures. Its outturn, the weight of clean coffee from a given weight of fruit, is much better.<sup><a href=\"#src-s2\">2</a></sup> A 2023 review gives 7 kg of fresh fruit for 1 kg of clean coffee in Uganda.<sup><a href=\"#src-s2\">2</a></sup>\n\nNo controlled sensory study of the two species was opened for this entry. The sources describe their flavour in general terms only. A 2025 study says liberica and excelsa have contrasting flavour profiles.<sup><a href=\"#src-s1\">1</a></sup> A 2023 review describes Ugandan and South Sudanese excelsa as smooth, with low to medium acidity and low bitterness.<sup><a href=\"#src-s2\">2</a></sup> An older handbook describes liberica as more bitter than arabica and robusta.<sup><a href=\"#src-s6\">6</a></sup>\n\n<!-- deep-dive -->\n\n## From two varieties to three species\n\nThe species name carries the author citation *C. liberica* Hiern.<sup><a href=\"#src-s4\">4</a></sup> Until 2025 the consensus of taxonomic study was one species with two botanical varieties, var. *liberica* and var. *dewevrei*.<sup><a href=\"#src-s2\">2</a>,<a href=\"#src-s1\">1</a></sup> An alternative view treated *C. liberica* as one species with no subdivisions.<sup><a href=\"#src-s1\">1</a></sup>\n\nThe 2025 study combined genome-wide data, morphology and cleaned distribution records. It supports three species: *C. liberica*, *C. dewevrei* and *C. klainei*. *C. dewevrei* and *C. klainei* were reinstated as older names, which raised the count of known *Coffea* species from 131 to 133.<sup><a href=\"#src-s1\">1</a></sup> The same group published a perspective on liberica as a crop in 2022, “The re-emergence of Liberica coffee as a major crop plant”, in Nature Plants.<sup><a href=\"#src-s8\">8</a></sup> This entry did not open that paper; facts from it are cited through the 2023 review that summarises it.\n\nThe “excelsa” name causes confusion in trade. A 2023 review restricts it to plants of var. *dewevrei* from eastern Cameroon, the Central African Republic, eastern DR Congo and western Uganda. It notes that it is often applied to small- to medium-seeded liberica, particularly in Asia.<sup><a href=\"#src-s2\">2</a></sup> In Uganda, excelsa is mostly exported as robusta or mixed with it, partly because it is taken for a large-leaved robusta.<sup><a href=\"#src-s2\">2</a></sup>\n\nThe same review records a historical case of the confusion: field trials of “excelsa” in Uganda in 1915 and 1916 gave poor yields. The material, imported from Java in 1914, was liberica, judging by its large seeds.<sup><a href=\"#src-s2\">2</a></sup>\n\n## Reference values\n\n| Parameter | *C. liberica* (liberica) | *C. dewevrei* (excelsa) |\n|---|---|---|\n| Native range | Upper West Africa<sup><a href=\"#src-s1\">1</a></sup> | Central Africa to South Sudan and Uganda<sup><a href=\"#src-s1\">1</a></sup> |\n| Leaf, length × width (mean) | 16.7–30.2 × 5.6–10.4 cm (22.8 × 8.2 cm)<sup><a href=\"#src-s1\">1</a></sup> | 22.4–35.9 × 10–18 cm (29.5 × 14 cm)<sup><a href=\"#src-s1\">1</a></sup> |\n| Flowers per leaf axil | (2–)4–18(–24)<sup><a href=\"#src-s1\">1</a></sup> | (4–)6–40(–48)<sup><a href=\"#src-s1\">1</a></sup> |\n| Corolla lobes (most frequent) | 6–9(–12) (7)<sup><a href=\"#src-s1\">1</a></sup> | 5(–6) (5)<sup><a href=\"#src-s1\">1</a></sup> |\n| Fruit, length × width | (1.5–)1.8–3.4 × 1.7–3.3 cm<sup><a href=\"#src-s1\">1</a></sup> | 1.2–2.5 × 0.8–2.1 cm<sup><a href=\"#src-s1\">1</a></sup> |\n| Pulp (mesocarp) thickness | 4–9.5 mm<sup><a href=\"#src-s1\">1</a></sup> | 2–3.5 mm<sup><a href=\"#src-s1\">1</a></sup> |\n| Parchment (endocarp) thickness (mean) | 0.36–0.77 mm (0.57 mm)<sup><a href=\"#src-s1\">1</a></sup> | 0.22–0.41 mm (0.31 mm)<sup><a href=\"#src-s1\">1</a></sup> |\n| Seed, length × width (mean) | 9.5–18.3 × 6.5–12 mm (12.6 × 8.4 mm)<sup><a href=\"#src-s1\">1</a></sup> | 7.7–11.3 × 5.4–8 mm (9.3 × 6.6 mm)<sup><a href=\"#src-s1\">1</a></sup> |\n| Tree height | – | Around 10 m or more (Uganda)<sup><a href=\"#src-s2\">2</a></sup> |\n| Elevation | Mostly 10–500 m in cultivation<sup><a href=\"#src-s1\">1</a></sup> | 680–1,200 m observed in Uganda<sup><a href=\"#src-s2\">2</a></sup> |\n| Mean annual temperature | e.g. 24–27 °C in cultivation<sup><a href=\"#src-s1\">1</a></sup> | 24.4 °C, modelled for recorded locations in Uganda (range 23.5–25.2 °C)<sup><a href=\"#src-s2\">2</a></sup> |\n| Mean annual precipitation | e.g. 2,000–4,000 mm in cultivation<sup><a href=\"#src-s1\">1</a></sup> | Not established; drought tolerance from field observations<sup><a href=\"#src-s1\">1</a></sup> |\n| Harvest | – | January–April (Uganda)<sup><a href=\"#src-s2\">2</a></sup> |\n| Yield, clean coffee | – | 877 kg/ha (204 trees/ha) to 3,440 kg/ha (400 trees/ha), calculated from farmer-reported fruit yields per tree and a 7:1 outturn; rain-fed, low input (Uganda)<sup><a href=\"#src-s2\">2</a></sup> |\n| Red List | Least Concern (as cited in 2025); reassessment as Vulnerable suggested (2025)<sup><a href=\"#src-s1\">1</a></sup> | Least Concern by the 2025 study’s own assessment<sup><a href=\"#src-s1\">1</a></sup> |\n\nMorphology from Table 1 of the 2025 study, which also lists *C. klainei*.<sup><a href=\"#src-s1\">1</a></sup> A dash means no value was found in the sources opened for this entry.\n\n## Production as of 2026\n\nOnline sources often state that liberica and excelsa supply 1–2% of world coffee. The 2025 study calls this incorrect: those shares date from the late 19th century, when *C. liberica* stood with arabica as the second most important coffee of commerce.<sup><a href=\"#src-s1\">1</a></sup> Its authors put present production of the two species at probably less than 1,000 tonnes. Against about 10 million tonnes of arabica and robusta exported in 2024, that is about 0.01% of world exports.<sup><a href=\"#src-s1\">1</a></sup> No newer global estimate was found for this entry as of October 2026.\n\nExcelsa production is rising in India, and in Vietnam and Indonesia, where it supplements robusta.<sup><a href=\"#src-s1\">1</a></sup> In Uganda, a separate market for excelsa did not exist in 2023.<sup><a href=\"#src-s2\">2</a></sup>\n\n## Climate tolerance in detail\n\nField observations suggest that *C. dewevrei* has considerable drought tolerance, particularly compared with *C. canephora*. Its precipitation needs in cultivation have not been established in trials.<sup><a href=\"#src-s1\">1</a></sup> The 2023 review describes excelsa as more heat tolerant than wild and cultivated arabica, which grows at a mean annual temperature of 18–22 °C. It adds that its own climate analysis does not support such observations with confidence.<sup><a href=\"#src-s2\">2</a></sup> Excelsa has replaced robusta in some areas of Uganda, probably as a result of climate change.<sup><a href=\"#src-s1\">1</a></sup>\n\nExcelsa also yields more than liberica, because each tree bears more fruit. Its thinner pulp and parchment improve the outturn and the profitability of the harvest compared with liberica.<sup><a href=\"#src-s1\">1</a></sup>\n\n## Diseases and breeding\n\nAccording to a 2017 textbook chapter, *C. liberica* was planted less than *C. canephora* because of its sensitivity to *Fusarium xylarioides*, the cause of coffee wilt disease.<sup><a href=\"#src-s4\">4</a></sup> Coffee wilt disease was first reported on excelsa (var. *dewevrei*) in the Central African Republic in 1927. It later caused widespread damage to liberica and robusta across large areas of tropical Africa.<sup><a href=\"#src-s2\">2</a></sup> As of 2023, no coffee wilt disease had been reported on excelsa in Uganda, but its level of resistance still needs research.<sup><a href=\"#src-s2\">2</a></sup>\n\nAccording to the 2000 plant handbook, liberica is susceptible to leaf rust, though much less so than the other coffees.<sup><a href=\"#src-s6\">6</a></sup> Its genes have served arabica breeding. In Indonesia, crosses of liberica with arabica gave tetraploid and octoploid hybrids, notably “Kalimas” and “Kawisari”, with a high degree of leaf rust resistance. In India, such hybrids showed good yield potential and rust resistance.<sup><a href=\"#src-s2\">2</a></sup> Grafting results differ by study (see Contested).<sup><a href=\"#src-s5\">5</a>,<a href=\"#src-s2\">2</a></sup>\n\n## Conservation status\n\nAccording to the 2025 study, the IUCN Red List assesses *C. liberica* as Least Concern, in an assessment that reports natural occurrence in 17 countries. The study suggests that the narrower *C. liberica*, native to five countries, may warrant reassessment as Vulnerable. By its own assessment, *C. dewevrei*, with an extent of occurrence of 2,464,990 km² and an area of occupancy of 456 km², falls into Least Concern.<sup><a href=\"#src-s1\">1</a></sup> In Uganda, a draft national assessment in 2023 placed excelsa as Endangered.<sup><a href=\"#src-s2\">2</a></sup>\n\nThe index lists every accepted coffee species with its native range and Red List category. Search for “liberica” or “dewevrei”, or filter by region.\n\n<div data-figure=\"coffea-species-index\"></div>\n\n## Open questions\n\n- **Precipitation needs of excelsa.** Its drought tolerance rests on field observations; trials of its water needs are still required.<sup><a href=\"#src-s1\">1</a></sup>\n- **Coffee wilt resistance in excelsa.** No disease reports from Uganda as of 2023, but its level of resistance still needs research.<sup><a href=\"#src-s2\">2</a></sup>\n- **Flavour of the two species.** No controlled sensory comparison of *C. liberica* and *C. dewevrei* was opened for this entry; published descriptions are general.<sup><a href=\"#src-s1\">1</a>,<a href=\"#src-s2\">2</a></sup>\n\n## Key studies\n\n<div class=\"study\">\n<p><strong>Davis et al., 2025 – Liberica is three species.</strong> Combines genome-wide data, leaf, flower, fruit and seed measurements and cleaned distribution records to separate liberica, excelsa and C. klainei. Re-estimates world production of liberica and excelsa at under 1,000 tonnes and suggests new Red List categories.</p>\n<p class=\"meta\">Nature Plants 11, 1729–1738 · <a href=\"https://doi.org/10.1038/s41477-025-02073-y\">doi:10.1038/s41477-025-02073-y</a></p>\n</div>\n\n<div class=\"study\">\n<p><strong>Davis et al., 2023 – Uganda’s indigenous coffee resources.</strong> Reviews the wild coffee species of Uganda, including excelsa, with their distribution, climate, uses and conservation status. Documents the farmer-led shift from robusta to excelsa and its reasons.</p>\n<p class=\"meta\">Frontiers in Plant Science 13, 1057317 · <a href=\"https://doi.org/10.3389/fpls.2022.1057317\">doi:10.3389/fpls.2022.1057317</a></p>\n</div>\n\n<div class=\"study\">\n<p><strong>Faronny et al., 2026 – Liberoid coffee in Sumatra and Java.</strong> Measures the variation in plant and fruit traits of liberica and excelsa across landscapes in Indonesia, including lowland peat soils. Places their introduction in the colonial response to leaf rust.</p>\n<p class=\"meta\">Tropical Life Sciences Research, early view, 2026 · <a href=\"https://ejournal.usm.my/tlsr/article/download/7664/early_view/13370\">full text (PDF)</a></p>\n</div>"
}