Eggs of P. aztecus are demersal and spherical, measuring approximately 0.26 - 0.28 mm in diameter (Pearson 1939 IN: Larson et al. 1989). Hatching occurs with 24 hours. Larvae develop offshore through 5 naupliar, 3 protozoeal, and 3 mysis stages before metamorphosing into postlarvae (Cook and Murphy 1969, 1971). Several postlarval stages occur prior to metamorphosis to the juvenile stage. Larval development takes approximately 11 days at a temperature of 32? C, and approximately 17 days at a temperature of 24? C (Cook and Murphy 1969).In studies of wild Penaid populations, P. aztecus larvae are most commonly sampled below mid-depth. Protozoea of this species are likely to occur nearest the bottom, while postlarval stages occur at, or slightly above mid-depth. However, all stages ascend to surface waters with the onset of darkness.Postlarvae return to coastlines on surface current during late winter and spring (Bearden 1961). Recruitment studies in the Carolinas revealed that postlarval P. aztecus began entering sounds in North Carolina from October through May, with peak recruitment in March and April (Zamora and Trent 1968). In South Carolina, P. aztecus postlarvae are found in all months of the year, with recruitment peaking during February and March (Bearden 1961). Juveniles are collected beginning in mid-April and continuing throughout the summer months (Williams 1955). In one Texas study, Copeland and Truitt (1966) observed that spring recruitment peaks were greatest during evening flood tides.Young P. aztecus postlarvae enter estuaries on flood tides and migrate to shallow, low-salinity waters. Growth is rapid during the warmer summer months. As they grow, they begin migration into progressively more saline waters, eventually returning to offshore areas.