Erigeron sumatrensis (Asteraceae): a new alien species to the flora of Kosovo

Erigeron sumatrensis is a South American annual weed that has become widely established outside its native range, including much of Europe and the Balkan Peninsula. Despite its regional distribution, the species had not previously been confirmed for the flora of Kosovo. This study documents the first verified record of E. sumatrensis in Kosovo and provides initial data on its distribution and habitat preferences. Field surveys conducted in 2025 across a broad range of habitats recorded the species at least 29 localities, primarily along roadsides and highways, urban margins, construction sites, waste ground, abandoned fields and disturbed agricultural areas. Additional occurrences along riverbanks and alluvial corridors indicate an ability to extend beyond strictly anthropogenic habitats. Species identification was based on diagnostic morphological characters and comparison with regional floras, with voucher specimens deposited in the Herbarium of the University of Prishtina (UPH). The widespread occurrence of E. sumatrensis suggests that the species is already well established in Kosovo. Given its known invasive behaviour and its strong association with transport corridors and disturbed environments, early monitoring and management measures are recommended to limit further spread and potential ecological and agricultural impacts.