Induced spawning and early development in Malaysian Sea Urchin, Salmacis dussumieri

Abstract

The life cycle of the sea urchin can be arbitrarily divided into six distinct phases. (1) Fertilization, (2) early cleavage until pluteus, for which food is not required, (3) development of the feeding pluteus to mature larva, (4) development of the embryonic urchin inside the growing larva, (5) metamorphosis and (6) growth of the young urchir, into a mature adult. The complete life cycle takes more than half a year to complete, and the later stages of development are difficult to study. The present paper reports the first two stages of development. These two stages are the easiest to study and no special precaution is needed for the culture of the embryo. The embryo develops normally till the pluteus stage by using the nutrient supply from the eggs. Further development is a long and complicated process as reported by some investigators (Hinegardner, 1969; Harvey, 1956). The present study only covers two earliest stages which take only about two days to complete though the larvae are able to survive up to five days.