Regeneration of major cheliped after the mating season in the hermit crab Pagurus middendorffii

Abstract

Males of the hermit crab Pagurus middendorffii use their major cheliped in male–male contests during the reproductive season. This study examined whether autotomized major chelipeds were regenerated before, during or after the mating sea- son. We reared males that were experimentally induced to autotomize just before the mating season (October). During the mating season (November), few males molted even if they had autotomized their major cheliped. In contrast, males initiated a molt at the end of and after the mating season, and most of the autotomized males regener- ated their major cheliped before the end of the rearing period (December). This sug- gests that regenerated major chelipeds in this study affect events other than mating, particularly perhaps future shell acquisition associated with general activities such as predator avoidance, physiological tolerance and growth. Key words: Anomura, autotomy, major chela, molt, regro