Sexual Reproduction and Fission in the Sea Star Asterina Burtoni from the Mediterranean Coast of Israel

Dense populations of the small fissiparous starfish Asterina burtoni, which migrated from the Red Sea, are found on rocky shores in the northern Mediterranean coast of Israel. Small animals are rare in the population studied. The population is apparently maintained only by fissiparity which is most common in summer months. Only testes were found in histological sections from this population, spermatogenesis follows annual pattern, with spawning occurring at about the same time as the peak of fission. The importance of fissiparity in the migration and establishment of this population is discussed.