Effect of autotomy and regeneration of the chelipeds on growth and development in Petrolisthes laevigatus (Guérin, 1835) (Decapoda, Anomura, Porcellanidae)

Abstract

The capacity to discard and regenerate limbs under conditions of vital risk does increase the probability of survival. Eventually, however, this can negatively influence the performance of other aspects of fitness in the organism affected. The influence of autotomy and regeneration of one or both chelipeds on body growth and intermoult period in Petrolisthes laevigatus was studied; individuals in a broad range of sizes were captured and subjected to autotomy treatments in one or both chelipeds, contrasted against a control group without autotomy. Body growth was measured as the increment of the carapace width after a moulting event. At the same time, the duration of the intermoult was considered as the period of time between two succesive moults. Significantly higher values of response in body growth, intermoult duration, and growth rate were observed in the control group with respect to the group with autotomy treatments. In the growth responses, the phenomenon of suboptimal foraging can be discarded and therefore the more probable explanation for growth decrease is related to reduction of the intermoult period or for changes in the allocation of energy from overall growth processes into the limb regeneration process.