Chromosome set in crustaceans of the subclass facetotecta (Crustacea, Thecostraca) from the White Sea

摘要

Chromosome set in the larvae of crustaceans of the subclass Facetotecta was investigated. The larvae were collected in the White Sea, near the White Sea Biological Station of Moscow State University. The diploid set of the species studied contains 28chromosomes. However, the occurrence of 29 chromosomes in some specimens may indicate the presence of an unpaired sex chromosome. The presence of tetraploid somatic cells is characteristic of both Facetotecta and Ascothoracida. Information on chromosomesets in all taxa of the class Thecostraca is given. Evolution of the crustaceans of this class is connected with an increase in the number of chromosomes, most probably with tetraploidy.