ИСТИНА

Ostracoda are microscopic crustaceans whose body is enclosed in a calcareous bivalve shell. Their shells are well preserved in the fossil record. Shells of different sexes and ages can be distinguished, which is particularly informative for studying the evolution of ontogeny, sexual dimorphism and establishing relationships. And scanning electron microscopy (SEM) is one of the main tools to study both recent and fossil ostracods. We studied Middle Jurassic ostracods of the genus Lophocythere Sylvester-Bradley, 1948 from deposits of Central Russia, where the Central Russian Sea was at that time, in order to compile ontogenetic tables. The shell of all representatives is characterized by prominent sculpture in the form of spines and/or ribs, divided into meso- and macrosculpture. Each shell was examined by us externally and internally, under scanning electron microscopes of various designs. For each species, we compiled ontogenetic tables in which the shells from different time intervals were divided by age stages.