Two centuries of Begonia exploration in the Philippines: Progress and challenges associated with a megadiverse genus in the Global South

Societal Impact Statement Megadiverse genera represent the highest concentration of plant diversity, but these plants are also located primarily in countries in the Global South where huge gaps in botanical knowledge remain. This study summarized two centuries of Begonia collection records in the Philippines to show how historical events coincide with collection and taxonomic progress and drawbacks, and visualize areas where botanical collections can be further exerted. The findings emphasize how the advancement of our botanical knowledge is interconnected with local and global historical events and highlight the importance of the state of botany in countries like the Philippines in the global discussion of botanical research. To enhance the reach of this work, a Filipino language version of the paper is available in the (see Translation_FIL). Summary A plant genus is considered megadiverse if it contains 1000 or more species. Globally, only 28 plant genera meet this criterion, yet together they account for approximately 13.6% of all known plant species. However, most megadiverse genera are concentrated in the tropics, particularly in low‐ and middle‐income countries where botanical research often faces persistent logistical, institutional, and socio‐political challenges. Here, we review existing collections of Begonia , one of the largest megadiverse plant genera, focusing on species found in the Philippines. This review illustrates timing of historical events and broader structural factors that may have shaped the trajectory of botanical research in the country. We synthesized data from online biodiversity databases, herbarium specimens, archived collection routes, and recent and past fieldworks to examine spatial and temporal patterns of Begonia collection. Records from the 1800s to the present were plotted against major historical events, and these collection data were mapped to identify areas of intensive sampling and regions that remain poorly explored. We also reviewed the taxonomic history of Philippine Begonia sect. Baryandra to highlight the dynamic nature of classification in megadiverse genera. Collection records were sporadic during the Spanish colonial period, followed by a pronounced peak in the early 1900s coinciding with the establishment of the country's Bureau of Science. This surge was interrupted by war and political instability, resulting in prolonged stagnation, before a renewed increase in Begonia collections and publications in recent decades. The map of the spatial extent of collections revealed both well‐studied and poorly sampled localities, which further reveals which islands and localities can be prioritized for collection. A review of Begonia sect. Baryandra , a Philippine‐centered section, illustrates how limited data availability led to a century‐long stagnation in sectional delimitation, only resolved through recent integrative evidence. By synthesizing historical and contemporary data, this study aims to guide future fieldworks and encourage continued research on Begonia . This study also underscores how botanical research progress is closely intertwined with national socio‐economic and political contexts, viewed through a Global South perspective.