First record of Heptapleurum arboricola Hayata (Araliaceae) as a casual non-native woody plant in the Mediterranean area

Abstract

I report here the first record of Heptapleurum arboricola Hayata (syn. Schefflera arboricola (Hayata) Merr.) (Araliaceae) as a casual non-native plant throughout the Mediterranean area. I observed the natural regeneration in urban areas at Castellammare del Golfo, a small coastal town in north-west Sicily (Mediterranean Italy). Due to the lack of self-sustaining populations and the short-term observational period, Heptapleurum arboricola should be considered as a casual species according to the classification of non-native plants. The detection of early signs of naturalization of non-native plants is of crucial importance for the management and control of invasive species. The main abiotic and biotic factors involved in the possible future spread of the species are briefly discussed.