Colocasia esculenta (L.) Schott (Araceae), an expanding invasive species of aquatic ecosystems in the Iberian Peninsula: new records and risk assessment

Colocasia esculenta (L.) Schott, Araceae, is becoming an invasive plant in Spain (Iberian Peninsula). Four newly invaded localities are presented in this study, and its population status, habitat and climatic features in Spain are presented. The species has colonised some localities in south Portugal. To characterise the species' climatic tolerance, its world distribution was reviewed, and the climate types of other invaded areas worldwide were identified. Global data show that the species has the potential to colonise aquatic ecosystems under a wide variety of climate types. Finally, based on two different procedures, risk assessments were conducted for the Iberian Peninsula and for continental Europe. Both suggested a high ecological risk associated with this species. Caution is called for in terms of its use outside of its native distribution range. It is proposed that this species should be considered as invasive and risky to European and Iberian water bodies and should be legally banned in Europe.