Studies on the Cultured Phyllosoma Larvae of the Japanese Spiny Lobster, Panulirus japonicus-I

Morphology of the Phyllosoma

Abstract

The phyllosoma larvae of Japanese spiny lobster, Panulirus japonicus, was successfully reared in the laboratory up to the last stage of 29.6 mm in body length, fed on the nauplii and adults of Artemia salina, adults of Sagitta spp. and fish frys of several species, and it took 253 day after hatching.
The developmental state of appendages in each molt of these reared larvae was not always regular. After several molts, the larvae reached the size of next stage. Consequently, each instar did not mean a new stage.
It is not clear whether above mentioned developmental stages were caused only by the unfavorable rearing conditions or whether they actually occur under natural sea conditions as well.
According to the development of appendages and body proportions observed in 112 specimens obtained for this study, phyllosoma larvae of Panulirus japonicus were divided into 11 stages. The characteristics of each stage are described.
In 1963, the author reported that the phyllosoma could be divided into 14 stages since the author assumed that Form E of Panulid phyllosoma named by OSHIMA would be the same phyllosoma of Panulirus japonicus compared with the specimens obtained in artificially reared larvae. However it was clarified in the present study that this form of phyllosoma is not of Panulirus japonicus but of some other species. Accordingly, the author wishes to correct the number of phyllosoma stages given in his former report.