In the past two years, we have documented the appearance and rapid spread of several
grass species native to the Mediterranean regions of Europe in Transdanubia. Stands
of Anisantha diandra, Anisantha madritensis, Avena barbata, Catapodium marinum, Hainardia
cy- lindrica , and Parapholis incurva were identified along major roads, predominantly
on road edges, while Psilurus incurvus was discovered along a railway line. C. marinum
and P. incurva have emerged new, rapidly spreading non-native species along salted
road edges, capable of reaching greater distances in a short period. Based on its
initial behaviour, H. cylindrica shows significant invasive potential and poses a
potential threat to our native wet alkaline habitats. Anisantha diandra, A. madritensis
and Avena barbata are species showing dynamic spread in roadside weed communities.
Among the species discussed, this is the first report of Anisantha diandra, C. marinum,
H. cylindrica, Parapholis incurva , and Psilurus incurvus in Hungary, and several
of them are also new records for Central Europe. The occurrence of Avena barbata and
Anisantha madritensis has been confirmed in Hungary for the first time in a long period.
The emergence of a strong wave of species influx has been triggered by the operation
of the international transportation network (continuous habitat corridors, increased
road traffic), and climate change provides a favourable background for this phenomenon.
The species discussed are characterized by almost immediate establishment and, in
most cases, rapid population growth and invasion in their habitats.
