Drivers of floristic discovery in a temperate flora: insights from three decades of vascular plant records in Ukraine.

backgroundFloristic discoveries continue to occur even in regions with a long history of botanical exploration. Ukraine, one of the largest countries in Europe, has been the subject of intensive botanical study for more than two centuries, yet new species, subspecies, and national records are still regularly documented. Understanding the ecological and methodological factors that drive these discoveries is important for improving biodiversity assessment, guiding field surveys, and updating national floras. This study provides a comprehensive synthesis of all vascular plant taxa newly described for science or newly recorded from Ukraine during the period from 1997 to 2024 and identifies the principal drivers of floristic discovery in a temperate flora.

resultsA total of 331 species and subspecies of vascular plant were discovered or newly recorded during the study period, including 57 taxa described as new to science. These findings span lycopods, ferns, gymnosperms, and flowering plants, with flowering plants contributing the largest share. Synanthropic habitats, particularly those associated with human disturbance and escaped cultivated plants, yielded the highest number of discoveries. Grasslands, woodlands, stone outcrops, and coastal habitats also contributed substantially, while mountainous areas were notable centres for both newly described taxa and hybridogenic diversity. The majority of discoveries were based on material collected during spring and summer, although historical herbarium specimens, some over a century old, were essential for many taxonomic descriptions and for confirming previously overlooked taxa. Citizen science platforms supported several recent national records by enabling rapid detection and preliminary verification of unusual occurrences, although they have not yet contributed directly to the description of new taxa.

conclusionsOur findings highlight the continued incompleteness of floristic knowledge, even in well-studied temperate regions, and underscore the need for targeted survey strategies that integrate historical collections, underexplored habitats, and public participation. While Ukraine provides the case study, these patterns and methodological approaches are broadly applicable to biodiversity assessment and conservation planning in similar biogeographic contexts worldwide.