Discovered far from home: a new Medicago species (Fabaceae) of unknown origin, associated with historical wool imports in Belgium

Background and aims – A previously undescribed species of Medicago was discovered in Belgium. Its identification and characterization are important for understanding non-native plant introductions linked to historical human activities. Material and methods – Morphological traits of the single individual found were assessed and compared with related species.

Phylogenetic analyses were conducted using nuclear ITS and GA 3 ox 1 markers, as well as plastid matK sequences, to establish genetic relationships. Key results – Medicago peregrina sp. nov. displays a unique combination of morphological features distinguishing it from other Medicago species. Phylogenetic evidence supports its status as a novel taxon.

The species was found on a disturbed riverbank of the Vesdre River in Goffontaine, Belgium, following a major flood in 2021. The species is clearly non-native to the region and is likely associated with historical wool processing activities in the valley. Genetic affinities and the origins of imported wool suggest its native range lies in the Middle East and adjacent regions, although it has not yet been documented there.

Conclusion – The discovery of Medicago peregrina sp. nov. illustrates how historical trade can leave transient botanical traces and highlights the value of continued botanical surveys in disturbed habitats. This case emphasizes the need to consider historical human activity when interpreting the presence of non-native plants.