IMMATURE SHRIMP (DECAPODA, PENACIDAC) DISTRIBUTION IN THE ALVARADO LAGOON SYSTEM, VERACRUZ, MEXICO

Immature Penaeus aztecus and P. setiferus shrimp are distributed throu ghout the lagoonal system of Alvarado. The first species dominates wit h respect to density (58%) and biomass (91%). Both species are frequen t in the seagrass beds along the inner margin of the bar of Alvarado, where they tend to concentrate. P. aztecus density increased with mean monthly salinities greater than 11 parts per thousand while the oppos ite occured in the case of P. setiferus. Shrimp densities are consider ed low compared to other estuarine systems of the Gulf of Mexico. Such low densities are related to hydrological conditions and artisanal ov erfishing.