Larval period and molting in the Japanese spiny lobster Panulirus japonicus under laboratory conditions

A total of 325 pueruli of the spiny lobster Panulirus japonicus was successfully reared in the laboratory at Minami-Iku Station of Japan Sea-Farming Association, Shizuoka, Japan, during 1989-1997. Of these pueruli, 136 individuals metamorphosed into the first juvenile stage. The duration of the phyllosoma stage ranged from 231 to 417 days (mean 319.4 days), and it has a tendency to extend as the increase of water volume in the rearing tanks. The number of molting in the phyllosoma stage was 20-31. The body length of the last-stage phyllosoma ranged from 27.9 to 34.2 mm and the duration of the last stage was 11-26 days. The carapace length of the puerulus stage was 6.0-8.0 mm and the duration was 9-26 days. The present data and those of previous studies suggest that the body size and the duration of phyllosoma stage in captivity are affected by environment as in the field. The duration of the puerulus stage is considered to be controlled basically by water temperature and nutritional conditions in the phyllosoma.