The first record of the swordtailXiphophorus helleriiHeckel, 1848 (Poeciliidae, Actinopterygii) established in the wild from Morocco

Aquarium and ornamental fish trade is currently recognized as a major source of invasive species in aquatic ecosystems around the world. The swordtailXyphophorus helleriiis a popular ornamental freshwater fish that occurs as an introduced species in the aquatic habitats of at least thirty-one countries. We report the first finding of an established population of the swordtail in Morocco. Twelve individuals ofX. helleriiwere captured along Oued Ain Chkef inside the park (Fez Province), including females and males (mature and immature). Ongoing investigations could soon reveal more occurrences of this species in the country.