A review of Pseudoleptomesochrella Lang, 1965 (Copepoda, Harpacticoida, Ameiridae), including a redescription of P-halophila (Noodt, 1952) from the Black Sea and a key to species

Abstract

Both sexes of Pseudoleptomesochrella halophila (Noodt, 1952) (Copepoda, Harpacticoida, Ameiridae) are redescribed in detail based on material collected from the Black Sea coast of Turkey. Careful comparison revealed that the Turkish specimens are identical with the northwestern European populations originally reported from the Isle of Sylt (Germany) and the Isles of Scilly (U.K.). Re-examination of the type material of Nitocrella halophila brevifurca Wells, 1961 confirmed its conspecificity with P. halophila. Comparison of the various descriptions indicates the genus comprises two species complexes (Atlantic and P. halophila groups) whose members exhibit only cryptic differences, and that the majority of discrepancies reported in the literature are potentially unreal. Pseudoleptomesochrella pontica Apostolov, 1969 is removed from its synonymy with P. halophila and is reinstated as species inquirenda. A dichotomous key to species of Pseudoleptomesochrella Lang, 1965 is provided.