Histology of gills in the Black-scar oyster Crassostrea iredalie

Abstract

The objective of this study was to reveal anatomical and histological structure of the Black-scar oyster, Crassostrea iredalie gills. Oysters with shell length of 6-8 cm were randomly collected from the coasts of Chonburi Province. Results showed that the gills were classified as Pseudolamellibranch type. Four gill lamella, which originated form two gill axis comprising two pair. Each pair consists of inner and outer lamellae. The inner lamella are reflected on themselves and continue upward along the plane of the ascending lamella to fuse with visceral mass inferior to the common afferent vein. The outer lamella are also reflected but the edge of the plate fused with mantle next to branchial efferent vein. Water tubes are surrounded gill lamella to pass water by gill filament where gas exchange takes place. There are 12-14 gill filaments in the Black-scar oyster. According to gill architecture of the Black-scar oyster, it is indicated the function of gills are not only perform gas exchange but also function as food filter and gamete dispersal during spawning.