Elthusa poutassouiensis (Penso, 1939), comb. nov (Isopoda, Cymothoidae) for Meinertia (Ceratothoa) poutassouiensis, parasite of the blue whiting, Micromesistius poutassou

The parasite was obtained on the gill cavity of the blue whiting, Micromesistius poutassou (Risso), from the Aegean Sea Coast, Turkey. This cymothoid is a typical parasite of the blue whiting, but it is poorly known. It was reported from the same host as Meinertia (Ceratothoa) potassoniensis and Meinertia poutassouiensis with an inadequate description. The specimens examined in this study show the diagnostic characters of Elthusa Schioedte & Meinert, 1884. The previous two species are proposed to be transferred to the genus Elthusa. The ovigerous female, non-ovigerous female and male species are redescribed by drawings for the first time. The Mediterranean Sea is a new geographical record for the genus Elthusa.