Abstract

This study characterizes the stages of Jasus frontalis's moult cycle in base to external morphological changes of the caparace, as well as, setal development at tip of pleopods determining, in approximated form, the days that lack for ecdysis. At the beginning of the stage AB the exoeskeleton is found soft, but it begins to harden at the end of this stage. In this stage the epidermis is narrowly associated with the cuticle and the setal lumen presents a granular protoplasm. During stage C the caparace is totally rigid. In the state D occur the most important morphological changes associated with softenning of the caparace and with setal development. Due to this, the stage D is split into five substages (0 to 4). During the course of the substage D2, the plates B and C of the carapace begin to be softened, which can be easily depressed into the substage D4. The detection of external morphological characters constitutes an easy, quick and sure method to predict the moult process in the lobster Jasus frontalis, as well as, to detect potential females of being fertilized, that is, females that would provide thousands of eggs to the lobster's population. Due to this, the results of this investigation would allow to implement a new managing measure, tending to protect the reproductive potential of this species. This measure should consist in the prohibition of extracting females with their caparace lateral margins soft, due to the fact that these females would be sexually mature and next to the matching and/or spawning.