Parasitic copepods on immigrant and native clupeid fishes caught in Egyptian coastal waters off Alexandria.

Three species of parasitic copepods, one each from the siphonostomatoid families Lernanthropidae and Lernaeopodidae and one from the cyclopoid family Bomolochidae, are redescribed based on material collected from the gills of four fish species belonging to the family Clupeidae caught from coastal waters off Alexandria, Egypt. The recorded parasites are: Mitrapus oblongus (Pillai, 1964), found on Etrumeus teres (Dekay), an immigrant species from the Red Sea, and on Sardinella aurita Valenciennes, a native Mediterranean species; Clavellisa ilishae Pillai, 1962 found only on S. aurita; and Nothobomolochus fradei Marques, 1965 found on Herklotsichthys punctatus (Rüppell), an immigrant species from the Red Sea, and on Sardina pilchardus (Walbaum), a native Mediterranean species. The first two of these copepods have been reported before on clupeid hosts from the Indian Ocean. The third was known from the eastern South Atlantic and the Arabian Gulf. None of the copepods has previously been recorded in the Mediterranean. All of the parasites reported here constitute new records for these hosts. Two of the hosts are Erythrean (=Lessepsian) immigrants and were caught in Mediterranean waters off the Egyptian coast. The original description of N. fradei (Marques, 1965) is inadequate by modern standards. This species is fully described here for the first time. The male of M. oblongus was briefly described by Pillai (1964), but its mouthparts are described in detail here for the first time.