Size and Age Characteristics and Phenotypic Peculiarities of Somatic Growth of the Black Sea Mollusk Flexopecten glaber ponticus (Bivalvia, Pectinidae)

Abstract

This paper presents a preliminary analysis of the morphological, physiological, and biochemical parameters of somatic growth in the Black Sea scallop, Flexopecten glaber ponticus Bucguoy, Dautzenberg et Dollfus 1889, from a coastal site near Sevastopol, Crimea. The species is one of the few marine Black Sea mollusks listed in the Red Book of Sevastopol and Crimea with the status “Diminishing in numbers.” The peculiarities of soft tissue somatic growth have been studied in three size groups differing in linear diameter: 13–17, 21–24, and 25–30 mm. An analysis of the total RNA in tissue homogenates has shown that the rate of protein synthesis in the first and second groups (under-yearlings) is 1.2–1.5 times higher compared to adults. The population reveals seven color morphs (phenotypes). Three phenotypes (beige, violet, and gray-and-brown) are characterized by high-level protein synthesis. Mollusks of a mixed “multi” phenotype have the lowest level of tissue biosynthesis, usually being 2.5 times lower than that for other morphs. The results obtained indicate that the growth processes are linked to the color of the mollusk shell. High direct correlations between the weights of the total wet mass and the tissue mass observed in all mollusk groups may be evidence of positive growth allometry.