抄録
Larvae of the Japanese glass shrimp, Pasiphaea japonica Omori, 1976 were described for the first time on the basis of laboratory-reared material. The larvae hatched from incubated eggs detached from pleopods of females collected in Toyama Bay, Japan and were classified into four larval stages based on morphological characteristics. With respect to caridean larval morphology, this species is remarkable for the presence of a small spinule on the opposite side of the long natatory seta below the tip of the exopods of the maxillipeds 2 and 3 at larval stage 1. Newly hatched larvae swam smoothly backwards by means of the maxillipeds, with the telson directed forwards. Decapodids metamorphosed from larvae swam forwards using pleopods. It took 8-13 days to metamorphose to the decapodid stage at 13℃ and 19 days at 10℃, respectively. In contrast, no larva metamorphosed to decapodid stage at 5℃. Feeding behavior was not observed during the larval stages and there were no remarkable change in mandible and maxillule. Moreover, one larva was able to metamorphose to decapodid stage without feeding.