Taxonomic revision of the Nitocra affinis Gurney, 1927 species complex (Harpacticoida, Ameiridae) with descriptions of four new species and re-evaluation of its subspecies

Abstract

Due to the recent increasing importance of microcharacters in copepod taxonomy, it has become evident that many species lacking detailed descriptions actually constitute to a species complex. In this study, Nitocra affinis is redescribed based on lectotype material from Lake Timsah (Egypt) which facilitated a thorough detailed comparison with specimens of N. affinis recorded from distantly related localities. The results unequivocally revealed that the specimens of N. affinis examined in this study belong to a different species. As a result, four new species, Nitocra sonmezi sp. nov. and Nitocra serdarsaki sp. nov. from the Turkish coast, Nitocra alperi sp. nov. from the Indian Ocean, and Nitocra loweae sp. nov. from Brighton, England are herein described as new to science. On the other hand, all subspecies of N. affinis, namely N. affinis rijekana Petkovski, 1954, N. affinis californica Lang, 1965, N. affinis stygia, Por. 1968, and N. affinis colombiensis Fuentes-Reinés & Suárez-Morales, 2014 are elevated to species rank. An updated key the species of the affinis group is also provided.