On the occurrence of Eudiaptomus gracilis (G.O. Sars, 1863) (Copepoda: Diaptomidae) in Madeira (Portugal)

Calanoid copepods belonging to the diaptomid genus Eudiaptomus Kiefer, 1932 were collected in an artificial water body on the island of Madeira, Portugal. The morphological and molecular identification of the collected specimens unequivocally proved that they belong to the allochthonous species Eudiaptomus gracilis (G. O. Sars, 1863), possibly unwarily introduced along with fish stockings or ornamental aquatic plants. In the sampled site, the species co-occurred with the non-native cyclopoid copepod Acanthocyclops americanus (Marsh, 1893) and some anomopod species. This is the first record of the species for Portugal and the whole Macaronesia, whereas the possible presence of E. gracilis in the Iberian Peninsula should be verified.