The larval development of the Asian clam, Corbicula fluminea in the hatchery

Abstract

The larval stage is given high priority in seed production, which is an essential aspect of any farming practice. Induced breeding was carried out by integrating temperature, salinity, and gametes suspension. Individuals from spawning broodstocks were sacrificed to observe larval development at an early stage. The released larvae (veliger) development was monitored until they settled on the substrate. As a result, three developmental stages have been identified: marsupial, planktotrophic, and benthic. The marsupial stage lasts until the pediveliger (D-shaped with velum and developed ciliated foot) is brooded in the innerdemibranches. The planktotrophic stage begins when the broodstocks release the first straight-hinged veliger (D-shape). Finally, the juveniles reach the benthic stage when they start to settle at thebottom of the culture chamber. Before metamorphosing into planktonic juveniles, the veligers were nurtured for about a month. Internal organs such as double-looped gills, digestive, mantle, foot, and prominent shell ridges developed and matured in planktonic juveniles. Therefore, the documentation of C.fluminea larval revealed significant development stages for seed production in the hatchery conditions.