Effect of salinity change on early development in Galeolaria caespitosa (Polychaeta : Serpulidae)

Abstract

Although G. caespitosa is able to survive seawater dilution down to 60% seawater, oocytes released into 60% seawater are not viable. Despite this, a greater percentage of oocytes released into 60% seawater are induced to undergo prematuration (as indicated by the initiation of meiosis) than occurs in oocytes released into normal seawater. Unspawned oocytes in adult worms maintained in 60% seawater are protected from this osmotic shock despite equilibration of the osmotic concentration of the body fluids with the external medium.