The larvae of the spider crab Pisoides bidentatus (A. Milne-Edwards, 1873) (Decapoda: Majoidea: Pisidae) reared under laboratory conditions

Larval development of the spider crab, Pisoides bidentatus (A. Milne-Edwards, 1873) (Decapoda: Majoidea: Pisidae), inhabiting the Russian waters of the Sea of Japan is described and illustrated for the first time from larvae reared in the laboratory. The development included two zoea and one megalopa, thus following the typical pattern in the Majoidea. At a temperature of 20–228C larval development of P. bidentatus took from 9 to 13 days. The comparative analysis revealed that the larvae of two Pisoides species differ in numerous characters whereas zoea of P. bidentatus and Pugettia quadridens belonging to different families are nearly identical. According the larval characters, P. bidentatus and P. quadridens should be assigned to one genus. The larval data lend the support to revision the taxonomic position of P. bidentatus.