Long-Lived Larvae of the Gastropod Aplysia juliana: Do They Disperse and Metamorphose or Just Slowly Fade Away

The planktonic larvae of the opisthobranch Aplysia juliana stop growing about 30 d after release from the egg niass.Both tissue and shell mass remain at a plateau in excess of 200 d.During this pel-~od larvae swim, feed dnd renlaln conlpetent to metamorphose.Mortality of larvae in long-term cultures appears to be due to envlronn~ental factors rather than senescence.T h e potential duration of larval life suggests that these larvae are capable of long-d~stance dispersal by major ocean currents.