EARLY AND LARVAL DEVELOPMENT OF THE CHILEAN GIANT MUSSEL CHOROMYTILUS CHORUS (BIVALVIA, MYTILIDAE)

Abstract

Ch. chorus adults were induced to spawning through termic and Chemical stimuli (KC10,5 M). Fertilization was done to continué with larvae culture until the seed fixation occurs. Larvae were fed daily with monoalgae culture of Isochrysis galbana, Monochrysis lutheri or Pseudoisochrysis sp. in a concentration of 30.000 cel/ml during the first week of vcliconcha and of 50.000 cel/ml during the rest of the time. The culture temperature was 16.5°C and salinity fluctuated between 23and 25%o. The trochophore larva appears after 19 hours and its shell stars to come out 3 days later. The umbo stage is observed at the 7th day, its eye at the 25th day and the larval fixation occurs at the 27th to 32 th day when the larva has reached a size superior to 300 um of maximun length.