METAMORPHOSIS OF LABORATORY-REARED LARVAE OF CONCHOLEPAS-CONCHOLEPAS (MOLLUSCA, GASTROPODA)

Metamorphosis of laboratory-reared larvae of the gastropod Concholepas concholepas was observed under the influence of K+ ions. After 64 h of incubation at 10 degrees C, 58% of larvae metamorphosed in response to 20 mM K+ final concentration in seawater, 11 mM above ambient. No effect was observed at 15 mM K+. Likewise, larvae were unable to survive when exposed to 25 mM K+. Metamorphosed individuals of C. concholepas migrated to the water-air interface within 28 h of their metamorphosis. This study reports the first successful experiment on the induction of metamorphosis in laboratory-reared larvae of C. concholepas. The advantages of mass production of larvae with metamorphic capacity of this economically important resource, related to its eventual culture on a pilot scale are discussed.