Systematics of Quaternary and recent marine ostracods (Arthropoda, Crustacea, Ostracoda, Podocopida) from South Africa. Part 1. Hemicytheridae, Trachyleberidae

The article is a continuation of systematic studies of marine ostracods of South Africa. The synonymies of the species Aurila dayii (Aurila strongyle “syn. nov.”) and Aurila petricola (Hemicythere? sp. “syn. nov.”) are proposed. For the first time, diagnostic characters of the species Hemicythere californiensis, Aurila petricola, Aurila kliei, and Mutilus bensonmaddocksorum have been identified. The presence/absence of the diagnostic “Aurila-Tooth” and its variability in the species Aurila dayii and Aurila petricola are discussed. SEM/DM images of generic and specific taxonomic characters are given. For the first time, sexual dimorphism of the shell was identified for the species Hemicythere californiensis and Urocythereis arcana, and supplemented for Aurila dayii, A. petricola, A. kliei, Mutilus bensonmaddocksorum, and M. malloryi. North Atlantic, North Pacific, and endemic zoogeographical groups of ostracods were identified, and it was concluded that endemics (70% of the total number of described species) dominate the biotopes of the southern and eastern coasts of South Africa. Data on the ecology, stratigraphic position, and geographical distribution of South African ostracods have been supplemented. Conclusions were made regarding the varying degrees of study of ostracods of the genera Hemicythere, Aurila, Mutilus, Urocythereis, and the need for further study of intraspecific variability, sexual dimorphism, and ontogenesis of ostracods in shell morphology, which are important for correct species identification.