Comparative Cytogenetics. 2007. 1(1): 63-69.
Genome sizes of some Bivalvia species of the Peter the Great Bay of the Sea of Japan
Abstract. By means of cytophotometry on squashed slides stained by Feulgen the 2C-value of DNA was determined in diploid nuclei of 12 bivalve species from 8 families of 2 subclasses (Pteriomorphia and Heterodonta) of the Peter the Great Bay of the Sea of Japan. It was found that 2C DNA mass of the species investigated varies from 1.82± 0.03 pg in Crassostrea gigas (Ostreidae) to 6.80 ± 0.06 pg in Modiolus kurilensis (Mytilidae). Average genome masses scarcely differ between two subclasses. However, within Pteriomorphia DNA content varies more significantly than within Heterodonta. In general, in subclass Pteriomorphia, a positive correlation between specialization ofspecies and low genome size takes place supporting the hypothesis that evolution of Bivalvia occurred through a morphological specialization and was accompanied withdecreasing of DNA amount.