When the male postlarva reached a size of approxi-mately 1cm carapace length (approximately 67days of
the postlarval stage) the appendix masculinae appeared
at the inner rim of the second pleopods (Fig. 1D). The
gonads of all the stage II male specimens (with the
gonopore complexes and the appendix masculinae)
differentiated into testes which were characterized by a
structure of spermatogenic lobules (Fig. 3A). All of the
specimens without the gonopore complexes and the
appendix masculinae were female, as characterized by
the gonads filled with oogonia (Fig. 3B).