New records in vascular plants alien to Tenerife (Spain, Canary Islands).

Fifteen taxa (Acacia decurrens, A. mearnsii, Caesalpinia pulcherrima, Ensete ventricosum, Eucalyptus camaldulensis subsp. arida, E. cladocalyx, Euryops chrysanthemoides, Ficus elastica, Lippia alba, Pavonia sepioides, Pittosporum tobira, Populus × canadensis, Pyrostegia venusta, Ruellia dipteracanthus and Wigandia kunthii) are reported for the first time from the Canary Islands. All were initially introduced on purpose, mostly as ornamentals, and recently started to escape from cultivation. Most of them are ephemerals or only locally established, but nearly all have the potential to naturalise in the future. Thirteen additional species are reported for the first time from Tenerife: Atriplex nummularia, Bellis perennis, Chenopodium probstii, Coccoloba uvifera, Commelina benghalensis, Cuphea hyssopifolia, Eragrostis virescens, Lemna minuta, Malvastrum corchorifolium, Plerandra elegantissima, Psidium guajava, Thunbergia alata and Urochloa subquadripara. Finally, some miscellaneous notes are provided on the presence of Balanites aegyptiaca, Callistemon viminalis, Grevillea robusta and Passiflora caerulea in Tenerife.