Acartia lefevreae is a species of copepod belonging to the family Acartiidae. This species was discovered when specimens previously identified as Acartia clausi were examined and found to belong to a separate species. Its range overlaps with that of A. clausi, being found in the western Mediterranean and the north east Atlantic as far north as the English Channel, but it tends to be found in more brackish habitats such as estuaries.