A groundbreaking genomic study, spearheaded by researchers at the Royal Botanic Gardens, Kew, in collaboration with partners in Uganda and Cameroon, has revealed a significant reclassification within the coffee genus. What was once considered a single species, Liberica, has been genetically proven to be comprised of three distinct species: C. liberica, C. dewevrei (commonly known as Excelsa), and the newly identified C. klainei. This scientific advancement, published on August 8, 2025, in the esteemed journal Nature Plants, holds profound implications for the future of coffee cultivation, conservation efforts, and our understanding of coffee biodiversity, particularly as the global climate undergoes transformative shifts. Furthermore, this research aims to rectify historical inaccuracies regarding the global contribution of Liberica and Excelsa to the world's coffee supply.

Insights into the Reclassification of Coffee Species

The journey to redefine these coffee species commenced with meticulous genetic analysis. Scientists sequenced 353 nuclear genes from 55 diverse plant samples, uncovering clear evolutionary divergences that correspond with observable physical traits and geographical distribution patterns. This extensive genomic data distinctly separates C. liberica and C. dewevrei (Excelsa), noting their non-overlapping natural habitats and significantly different climate preferences. The research team highlighted that the climate profiles of wild Liberica and Excelsa coffee varieties are remarkably dissimilar, underscoring their unique adaptations.

A notable outcome of this study is the formal recognition of C. klainei. Previously dismissed as a mere variant of C. liberica, C. klainei is now understood as a distinct species primarily found across West-Central African regions, including Cameroon, Gabon, and Angola. This newfound understanding of C. klainei paves the way for further investigation into its characteristics and potential uses.

From a commercial perspective, the redefined C. liberica and C. dewevrei (Excelsa) are now considered priority subjects for ongoing research, particularly concerning their viability for widespread cultivation. These species exhibit considerable promise for expanding coffee farming into regions where conventional Arabica or Robusta varieties may not thrive, especially in hotter, wetter, and lower-elevation environments. This adaptability positions them as crucial alternatives in a changing climate, offering resilience and diversification to the coffee industry.

However, this reclassification also carries serious implications for conservation. The native range of the now-redefined C. liberica has been found to be drastically smaller than previously estimated, encompassing only five West African nations. This represents a staggering 95% reduction in its known indigenous distribution, emphasizing an urgent need for targeted conservation initiatives to protect this vulnerable species.

Despite its previously understated role, Liberica coffee is experiencing a resurgence in popularity, particularly across Southeast Asian countries such as Malaysia, Indonesia, and Fiji. Simultaneously, Excelsa coffee is gaining traction in nations like Uganda, South Sudan, and Guinea. Its remarkable ability to flourish and yield commercially viable crops under elevated temperatures and prolonged periods of drought, compared to Robusta, makes it an increasingly attractive option for diversifying global coffee production. Cultivation of Excelsa is also expanding in India, Vietnam, and Indonesia, signalling a broader embrace of its unique attributes.

Beyond the scientific delineation of species, this research serves to correct long-held misconceptions within global coffee statistics. The prevailing notion that Liberica and Excelsa contribute 1-2% of the world's coffee supply, a figure rooted in late-19th-century commercial data, is now definitively refuted. The authors assert that current global production of Liberica and Excelsa combined is likely less than 1,000 metric tons, constituting a mere 0.01% of worldwide coffee exports. This correction is vital for an accurate understanding of the global coffee market and for informing future agricultural and economic strategies.

This study underscores the dynamic nature of scientific understanding and the profound impact that meticulous research can have on various sectors, from agriculture and economy to biodiversity conservation. The reclassification of these coffee species not only enhances our biological knowledge but also provides practical pathways for developing more resilient and diverse coffee farming systems in an era defined by environmental change. It highlights the importance of ongoing genetic research in safeguarding invaluable plant resources and ensuring the sustainability of critical industries like coffee production.

A Fresh Perspective on Coffee's Future Amidst Climate Challenges

As a passionate observer of the coffee industry and its intersection with environmental science, this comprehensive reclassification of Liberica and Excelsa coffee varieties is nothing short of revolutionary. It challenges long-held assumptions and illuminates a path forward for coffee cultivation in an increasingly unpredictable climate. The meticulous genomic analysis conducted by the Royal Botanic Gardens, Kew, provides not just scientific clarity but also a vital roadmap for sustainability. It’s inspiring to see how a deeper understanding of genetic diversity can unlock potential solutions to global agricultural challenges. For coffee lovers and industry stakeholders alike, this research signals a crucial pivot towards embracing and nurturing the rich, often overlooked, tapestry of coffee species, ensuring the resilience and vibrancy of our beloved beverage for generations to come. It’s a powerful reminder that in understanding the past and present, we can better cultivate a more secure future for coffee.