Shell species were identified according to Sharabati (1984) and the following measurements were made: shell weight (SW), shell aperture width (SAW) and shell aperture length (SAL). Shell internal volume (SIV) was determined by the amount of water required to fill the empty shell by means of a measuring pipette. The eggs were carefully removed from the pleopods and classified into developmental stages according to the methodology of Turra and Leite (2001): initial stage: stages 1 and 2, without eyes and yolk partially consumed; intermediate stage: stages 3 and 4, eye formation started and yolk partially consumed; final stage: stage 5, eyes formed and yolk totally consumed. They were then counted under a light stereomicroscope.